bluuebunny/crossref_metadata_2025 huggingface dataset:
Purification and Characterization of the β-Galactosidase of
Aeromonas formicans
Authors: Rohlfing S. R. , Crawford I. P.
Published: January 2020

Rohlfing
, S. R. (Western Reserve University, Cleveland, Ohio),
and I. P. Crawford
. Purification and characterization of the β-galactosidase of
Aeromonas formicans
. J. Bacteriol.
91:
1085–1097. 1966.—The β-galactosidase of
Aeromonas formicans
was purified by diethylaminoethyl cellulose chromatography and gel filtration on Sephadex G-200. The properties of the enzyme molecule were compared with purified β-galactosidase from
Escherichia coli
. The sedimentation coefficients and electrophoretic mobilities of the two enzymes were not significantly different; the electrophoretic mobility of urea-produced subunits of the two enzymes was also similar. The stabilities of the two enzymes to denaturing agents provided measurable differences;
E. coli
β-galactosidase is relatively more heat-stable and more resistant to the action of urea. The amino acid compositions of the two proteins revealed significant differences in several amino acids, particularly alanine, arginine, glycine, and leucine. The comparisons cited suggest that
A. formicans
and
E. coli
are not completely unrelated, for their β-galactosidases show considerable structural similarity.
Identification of Nutritional Components in Trypticase Responsible for Recovery of
Escherichia coli
Injured by Freezing
Authors: Moss C. Wayne , Speck M. L.
Published: January 2020

Moss, C. Wayne
(North Carolina State University, Raleigh),
and M. L. Speck
. Identification of nutritional components in Trypticase responsible for recovery of
Escherichia coli
injured by freezing. J. Bacteriol.
91:
1098–1104. 1966.—Freezing and storage of
Escherichia coli
at −20 C resulted in nonlethal or “metabolic” injury to a proportion of the surviving population. The injury was manifested as an increased nutritional requirement after freezing. Injured cells could not grow on a minimal agar medium, but could develop on Trypticase Soy Agar. The percentage of injured survivors varied among strains, but was little affected by altering the freezing menstruum. Trypticase was found to be the component in Trypticase Soy Agar responsible for the recovery of injured cells, and contained five closely related peptides that possessed most of the biological activity. Isolation of the peptides was accomplished by Sephadex gel chromatography, paper chromatography, and high-voltage paper electrophoresis. Hydrolysis of the peptides destroyed the ability to restore injured cells.
Growth of
Desulfovibrio desulfuricans
Under Heterotrophic and Anaerobic Conditions
Authors: Alico Robert K. , Liegey Francis W.
Published: January 2020

Alico, Robert
K. (St. Bonaventure University, St. Bonaventure, N.Y.),
and Francis W. Liegey
. Growth of
Desulfovibrio desulfuricans
, under heterotrophic and anaerobic conditions. J. Bacteriol.
91:
1112–1114. 1966.—Growth of
Desulfovibrio desulfuricans
was investigated under heterotrophic and anaerobic conditions. For initial growth to occur, it was found that the E
h
or redox potential must be at least 0 mv. Some carbon sources were tested, and those which could be metabolized by
D. desulfuricans
were pyruvate, lactate, glycerol, glyceraldehyde, and ribose. Observations were also made on the sulfate used during growth. Various amounts of sulfate were added and depleted within 48 hr. This may be correlated with the decline in growth. As the terminal electron acceptor was exhausted the organisms could not respire, and, with the subsequent energy depletion, the population decreased.
Genetic Determination of the O Antigens of
Salmonella
Groups B (4,5,12) and C
1
(6,7)
Authors: Mäkelä P. Helena
Published: January 2020

Mäkelä, P. Helena
(University of Helsinki, Helsinki, Finland). Genetic determination of the O antigens of
Salmonella
groups B (4,5,12) and C
1
(6,7). J. Bacteriol.
91:
1115–1125. 1966.—The genetic determination of the O antigens of
Salmonella
was studied by Hfr or F′ crosses between strains of groups B (antigens 4,5,12) and C
1
(antigens 6,7). The main genetic determinants of the specificities 4 of group B and 7 of group C
1
behaved as alleles of one locus, called
O
or
O–4/7
. This is probably identical with
O–4/9
, responsible for the serological difference between groups B and D, and with the “rough” locus
rouB
. At least parts of the antigens 12 of group B and 6
2
of group C are determined at the same locus. The gene
O–5
is closely linked to
O–4/7
, both mapping in the approximately 2 minutes distance between
his
and
metG
in the order
his - O–4/7 - O–5 - metG
. In crosses of group B donors with group C
1
recipients, a serologically new type, called semirough (SR), appeared in most recombinants that had inherited the
O-4
allele of the group B donor. These SR forms are serologically intermediate between smooth and rough forms, showing poor stability in saline but possessing the specificities 4 and 12 and (some of them) 5. On the basis of previous biochemical studies, the hypothesis has been put forward that the side chains of their lipopolysaccharide are much shorter than normal group B side chains, probably containing only one repeating unit per side chain. A gene
SR-4
responsible for the elongation of group B side chains beyond the first repeating unit was mapped between
gal
and
try
, group B and D bacteria being
Sr-4
+
, and group C being
SR-4
−
.
Synthesis of the Enzymes of the Mandelate Pathway by
Pseudomonas putida
III. Isolation and Properties of Constitutive Mutants
Authors: Hegeman G. D.
Published: January 2020

Hegeman
, G. D. (University of California, Berkeley). Synthesis of the enzymes of the mandelate pathway by
Pseudomonas putida
. III. Isolation and properties of constitutive mutants. J. Bacteriol.
91:
1161–1167. 1966.—Mutants of
Pseudomonas putida
constitutive for the synthesis of
l
(+)-mandelate dehydrogenase were obtained after mandelate- or benzoylformate-limited growth in a chemostat. When grown in media noninducing for the wild type, the mutants are capable of coordinate, constitutive synthesis of the first five enzymes of the mandelate pathway. Later enzymes of the pathway that were examined are normally repressed. The constitutive mutants have two other noteworthy properties: they are superinducible by some compounds which induce the mandelate group enzymes in the wild type, or as a result of exhaustion of the carbon and energy source of the medium in which they are grown; and they exhibit a decreased specificity of induction, being inducible by a wide range of compounds devoid of inductive function for the wild type. These results, together with other evidence indicating that the five mandelate group enzymes comprise a regulatory unit, are discussed and evaluated in the context of the general problem of the regulation of complex dissimilatory pathways.
Response of
Bacillus
Spores to Combinations of Germinative Compounds
Authors: Foerster Harold F. , Foster J. W.
Published: January 2020

Foerster, Harold
F. (University of Texas, Austin),
and J. W. Foster
. Response of
Bacillus
spores to combinations of germinative compounds. J. Bacteriol.
91:
1168–1177. 1966.—Spores of 21 strains of
Bacillus megaterium
and 25 other strains representing 13 species of
Bacillus
were produced under standardized conditions. The germination of a washed spore suspension of each strain was measured as a response to various combinations of 30 different germinative compounds. The strains were first typed with respect to their response to “primary” germination compounds, i.e., glucose,
l
-alanine, inosine, and
l
-alanine-inosine mixture, and also Na
+
and K
+
. The second stage was the determination of the response to various organic and inorganic anions and cations, each strain being supplied with the “primary” compounds best for it. Marked differences in germination patterns were observed among species and strains of the same species. No relation to established taxonomic lines was evident. A nonspecific requirement for ions was found for all strains, but not all ions were effective. A striking degree of interchangeability of germinative chemicals was found. “Fractional germination” was very common. A mixture of
l
-alanine and inosine and various ions was the best germinative solution for most strains. Some anomalous germination patterns were encountered. Those studied included a strain whose cells lysed spontaneously upon germination and other strains for which
l
-leucine had striking germinative powers.
Cleavage of
S
-Ribosyl-
l
-Homocysteine by Extracts from
Escherichia coli
Authors: Duerre John A. , Miller Chris H.
Published: January 2020

Duerre, John
A. (University of North Dakota, Grand Forks),
and Chris H. Miller
. Cleavage of
S
-ribosyl-
l
-homocysteine by extracts from
Escherichia coli
. J. Bacteriol.
91:
1210–1217. 1966.—Cell-free extracts prepared from
Escherichia coli
catalyze the cleavage of the thioether linkage of
S
-ribosylhomocysteine. One of the products has been identified as homocysteine by paper chromatography of the
N
-ethyl-maleimide derivative and can be measured directly in reaction mixtures by sulfhydryl reagents. The other compound has been tentatively identified as ribose by column chromatography. Free sulfhydryl groups were also detected with use of
S
-adenosylhomocysteine as substrate; however, enzymatic cleavage of the glycosidic linkage of this compound appears to be required prior to cleavage of the thioether linkage. Homocysteine formed from either substrate could be converted readily to methionine, provided the necessary cofactors were added. Some of the properties of the ribosylhomocysteinase are discussed.
Interferon Production and Protein Synthesis in Chick Cells
Authors: Friedman Robert M.
Published: January 2020

Friedman, Robert
M. (National Cancer Institute, Bethesda, Md.). Interferon production and protein synthesis in chick cells. J. Bacteriol.
91:
1224–1229. 1966.—Overnight incubation of chick embryo fibroblasts (CEF) at 4 C before infection with live Semliki Forest virus (SFV) increased virus yields but decreased interferon production. The same findings were noted when CEF were incubated for 4 hr with
p
-fluorophenylalanine (FPA) before infection with live SFV or inactivated Chikungunya virus. In both systems incorporation of C
14
-leucine into protein appeared to be increased after pretreatment at 4 C or with FPA. Protein synthesis could be raised in CEF incubated in 0.5% serum after trypsinization by increasing the concentration of serum. CEF in 10% serum had higher rates of C
14
-leucine incorporation than did cells in 1.5% serum, but again the cells with the apparently high rate of incorporation produced less interferon. These findings may be related to the mechanism of cellular control over interferon production.
Effect of Interferon on Polymerization of Single-Stranded and Double-Stranded Mengovirus Ribonucleic Acid
Authors: Gordon Irving , Chenault Sara S. , Stevenson Douglas , Acton Jean D.
Published: January 2020

Gordon, Irving(University of Southern California, Los Angeles),Sara S. Chenault, Douglas Stevenson, and Jean D. Acton. Effect of interferon on polymerization of single-stranded and double-stranded mengovirus ribonucleic acid. J. Bacteriol.91:1230–1238. 1966.—The effect of interferon on actinomycin-resistant mengovirus ribonucleic acid (RNA) replication in L cells was investigated to determine whether defective or partially polymerized RNA products were made and whether synthesis of any specific class of virus RNA was prevented. RNA labeled with uridine-C14was extracted in hot and cold phenol and analyzed by zonal sucrose density centrifugation. Both single- and double-stranded infectious RNA peaks were identified. Interferon treatment caused almost complete depression of uridine-C14incorporation throughout linear sucrose gradients except in the 4Sregion, and no infectivity was detectable in any fraction. These inhibitory effects are attributable to the action of interferon, because they were reversed when cultures were treated with actinomycin D simultaneously with interferon. The results, with those of other investigators, indicate that the step at which interferon interrupts virus multiplication is between the events immediately after uncoating and the formation of template “minus” strands; under the conditions of our experiments, no partially polymerized virus RNA products were made.
Effect of Dark Repair on Ultraviolet Sensitivity of Bacteriophage-Infected Bacteria
Authors: Feiner R. R. , Hill R. F.
Published: January 2020

Feiner
, R. R. (Columbia University, New York, N.Y.),
and
R. F.
Hill
. Effect of dark repair on ultraviolet sensitivity of bacteriophage-infected bacteria. J. Bacteriol.
91:
1239–1247. 1966.—Changes in ultraviolet (UV) sensitivity of phage-host complexes during phage development have been studied for the following systems: T1 and
Escherichia coli
B, T1 and
E. coli
K-12S, λ and
E. coli
K-12S. Complexes were formed with bacterial strains differing in ability to dark-repair UV damage to deoxyribonucleic acid and, after irradiation, were plated on bacteria differing similarly. In the first half of the latent period, the resistance of complexes formed with nonrepairing bacteria increased considerably; with T1 and
E. coli
B hcr
−
, in 4 min the resistance became the same as that of complexes formed with repairing bacteria. The repair ability of plating bacteria affected survival curves only upon irradiation in the second half of the latent period after mature phages were present in the initial complex. Use of nonrepairing bacteria both for initial infection and for plating of late complexes resulted in a series of survival curves showing for all three systems the same pattern of change originally reported for T2-
E. coli
B complexes. Thus, a hitherto unexplained difference between radiation survival curves for T-even and T-odd phages seems due to repair of T-odd phages by the host.
Complement-Fixation Tests with Cell Lines Derived from Burkitt's Lymphoma and Acute Leukemias
Authors: Armstrong Donald , Henle Gertrude , Henle Werner
Published: January 2020

Armstrong, Donald(Children's Hospital of Philadelphia, Philadelphia, Pa.),Gertrude Henle, and Werner Henle. Complement-fixation tests with cell lines derived from Burkitt's lymphoma and acute leukemias. J. Bacteriol.91:1257–1262. 1966.—Cells of various lines isolated from Burkitt's lymphomas and acute leukemias and disintegrated by freezing and thawing or sonic treatment were found to react in complement-fixation tests with a considerable proportion of human sera. At least 107cells per milliliter were required for antigenic activity. All but one of 13 sera from Burkitt lymphoma patients were positive, with titers ranging from 1:8 to 1:320. About 20% of sera from American children and 60% of sera from adults, regardless of diagnosis, showed titers in a similar range. Sera giving positive tests with one of the neoplastic white cell antigens usually reacted also with many if not all of the others, but rarely with antigens derived from normal peripheral leukocyte cultures and not at all with HeLa or other human nonleukocytic cells. Various observations indicate that the complement-fixation test measures mainly antigens which are different from those detected by immunofluorescence. The nature of the reactions described remains obscure.
Biophysical Studies of Respiratory Syncytial Virus I. Density of Respiratory Syncytial Virus and Associated Complement-Fixing Antigens in a Cesium Chloride Density Gradient
Authors: Coates Helen V. , Forsyth Ben R. , Chanock Robert M.
Published: January 2020

Coates, Helen
V. (National Institute of Allergy and Infectious Diseases, Bethesda, Md.),
Ben R. Forsyth, and R. M. Chanock
. Biophysical studies of respiratory syncytial virus. I. Density of respiratory syncytial virus and associated complement-fixing antigens in a cesium chloride density gradient. J. Bacteriol.
91:
1263–1269. 1966.—Concentrated fluids from respiratory syncytial (RS) virus-infected tissue cultures (HEp-2 and BEK) were subjected to equilibrium sedimentation in cesium chloride. When two antigenically distinct strains of RS virus (Long and 18537) were tested, approximately 90% of the infectious virus was recovered in a sharp, symmetrical peak with a density of 1.22 to 1.24. In a similar study, unconcentrated virus had a density of 1.25 to 1.27. Two immunologically distinguishable complement-fixing antigens (antigens A and B) were detected at densities of 1.28 to 1.32 and 1.23 to 1.37. In addition, the existence of a third antigen (density of 1.22 to 1.30) was suggested. The possible origin of these antigens is discussed relative to the known properties of RS virus and the other myxoviruses.
Fine Structure of Bacteroids in Root Nodules of
Vigna sinensis, Acacia longifolia, Viminaria juncea
, and
Lupinus angustifolius
Authors: Dart P. J. , Mercer F. V.
Published: January 2020

Dart, P. J.
(University of Sydney, Sydney, Australia),
and F. V. Mercer
. Fine structure of bacteroids in root nodules of
Vigna sinensis, Acacia longifolia, Viminaria juncea
, and
Lupinus angustifolius
. J. Bacteriol.
91:
1314–1319.—In nodules of
Vigna sinensis, Acacia longifolia
, and
Viminaria juncea
, membrane envelopes enclose groups of bacteroids. The bacteroids often contain inclusion granules and electron-dense bodies, expand little during development, and retain their rod form with a compact, central nucleoid area. The membrane envelope may persist around bacteroids after host cytoplasm breakdown. In nodules of
Lupinus angustifolius
, the membrane envelopes enclose only one or two bacteroids, which expand noticeably during development and change from their initial rod structure.
Bacteriophage Infecting the Myxobacterium
Chondrococcus columnaris
Authors: Kingsbury David T. , Ordal Erling J.
Published: January 2020

Kingsbury, David
T. (University of Washington, Seattle),
and Erling
J.
Ordal
. Bacteriophage infecting the myxobacterium
Chondrococcus columnaris
. J. Bacteriol.
91:
1327–1332. 1966.—During a series of screening experiments, seven bacteriophages which infect the pathogenic myxobacterium
Chondrococcus columnaris
were isolated. Of these, one was chosen for detailed study. This phage has a wide host range among strains of
C. columnaris
, but does not infect other myxobacterial species tested. Morphologically, this phage resembles coliphage T2, though it is smaller. It has a head diameter of 600 A, a tail length of 1,000 A, and a tail width of 200 A. The head is attached to the tail by a well-defined neck. The turbid plaques produced by this phage are similar in appearance to those produced by coliphage λ, and average 1 mm in diameter. The phage has a latent period of 100 min, a rise period of an additional 90 min, and a burst size of 23. Calcium ions at a concentration of 0.004
m
are required for adsorption. This requirement cannot be met by substitution of magnesium ions. A purified preparation of 2 × 10
12
phage particles was extracted with phenol, and the nucleic acid was identified as deoxyribonucleic acid (DNA). Base ratios of the phage DNA and the DNA of two propagating strains were similar. Streptomycin at a concentration of 70 μg/ml inhibits phage infection at an early stage, probably by inhibiting injection of the phage DNA.
Induction of Penicillinase by Staphylococci In Vitro and In Vivo
Authors: Eyckmans Luc , Hook Edward W.
Published: January 2020

Eyckmans, Luc(Cornell University Medical College, New York, N.Y.),and Edward W. Hook. Induction of penicillinase by staphylococci in vitro and in vivo. J. Bacteriol.91:997–1003. 1966.—Staphylococci in mice with peritoneal infection showed no significant increase in penicillinase activity 6 hr after administration of penicillin G. In contrast, induction of penicillinase was readily demonstrated in leukopenic animals under similar conditions. Induction of penicillinase by staphylococci in vitro was inhibited by including leukocytes and immune serum in the mixtures. The role of leukocytes in inhibiting induction of penicillinase by staphylococci in response to penicillin was investigated.
Reversal of the Bactericidal Reaction of Serum by Magnesium Ion
Authors: Muschel Louis H. , Jackson Jean E.
Published: January 2020

Muschel, LouisH. (University of Minnesota, Minneapolis),and Jean E. Jackson. Reversal of the bactericidal reaction of serum by magnesium ion. J. Bacteriol.91:1399–1402. 1966.—Magnesium ion was found to reverse the bactericidal action of the antibody-complement system. Concentrations of 0.03 to 0.11mMgSO4or MgCl2were effective, provided that the reaction of the antibody-complement system did not proceed longer than 50 min. Salts of other monovalent and divalent cations, the polyamine, spermine, and several anticomplementary substances were inactive in reversing the serum bactericidal reaction. Thus, the bactericidal reaction of serum may be bacteriostatic under certain conditions, and this finding is compatible with the persistence of infection in certain diseases despite high levels of antibody.
Frequency of Occurrence of Native Hapten Among Enterobacterial Species
Authors: Anacker R. L. , Bickel W. D. , Haskins W. T. , Milner K. C. , Ribi E. , Rudbach J. A.
Published: January 2020

Anacker
, R. L. (Rocky Mountain Laboratory, Hamilton, Mont.),
W. D. Bickel, W. T. Haskins, K. C. Milner, E. Ribi, and J. A. Rudbach
. Frequency of occurrence of native hapten among enterobacterial species. J. Bacteriol.
91:
1427–1433. 1966.—Smooth cultures of representative
Enterobacteriaceae
were screened for the presence of native hapten, a substance previously extracted with trichloroacetic acid from the protoplasmic fraction of one strain each of
Escherichia coli
O111:B4 and O113. Trichloroacetic acid extracts of protoplasmic fractions of the cells were analyzed for chemical composition, for constituent sugars by paper chromatography, for immunochemical relationship to endotoxin purified by gel filtration, for sedimentation behavior, and for pyrogenicity in rabbits and lethal toxicity in chick embryos. Extracts from two of three additional strains of
E. coli
O113, all five additional strains of
E. coli
O111:B4, and one strain each of
E. coli
O26:B6 and O55:B5 were similar to previously described native hapten in chemical composition, sedimentation properties (
S
20,w
, 3.7 to 5.2), biological potency (usually less than 0.1% that of corresponding endotoxin), and immunochemical relationship to endotoxin. Extracts of one strain each of
E. coli
O127:B8,
Serratia marcescens, Citrobacter freundii, Salmonella enteritidis
, and of two lipopolysaccharide-deficient mutants of
S. enteritidis
differed from typical native hapten. The biosynthetic relationship of native hapten to endotoxin has not yet been revealed.
Action of Phenethyl Alcohol on the Synthesis of Macromolecules in
Escherichia coli
Authors: Prevost C. , Moses V.
Published: January 2020

Prevost
, C. (University of California, Berkeley),
and V. Moses
. Action of phenethyl alcohol on the synthesis of macromolecules in
Escherichia coli
. J. Bacteriol.
91:
1446–1452. 1966.—A kinetic study of the effects of various concentrations of phenethyl alcohol on the synthesis of ribonucleic acid (RNA), deoxyribonucleic acid (DNA), protein, and β-galactosidase in
Escherichia coli
has confirmed that RNA synthesis, rather than DNA synthesis, is first and most affected by phenethyl alcohol. The presence of inducer did not protect β-galactosidase synthesis from inhibition by phenethyl alcohol. Little preferential inhibition of β-galactosidase synthesis was observed; this is in contrast to the severe catabolite repression which results from partial inhibition of total protein synthesis caused by chloramphenicol or starvation for a required amino acid. We found no evidence that messenger RNA synthesis was inhibited to a greater extent than total RNA synthesis.
Methylated Bases in the Host-Modified Deoxyribonucleic Acid of
Escherichia coli
and Bacteriophage λ
Authors: Gough Michael , Lederberg Seymour
Published: January 2020

Gough, Michael
(Brown University, Providence, R.I.),
and Seymour Lederberg
. Methylated bases in the host-modified deoxyribonucleic acid of
Escherichia coli
and bacteriophage λ. J. Bacteriol.
91:
1460–1468. 1966.—The deoxyribonucleic acid (DNA) from strains of
Escherichia coli
and phage λ was examined to determine whether the types or amounts of methionine-derived methylated bases present correlated with the host-specific modification of that DNA. The DNA of strain C600 (which has K-12 modification specificity) and of a modificationless mutant of C600 are similar in their content of 5-methylcytosine and 6-methylaminopurine. Strains Bc251 and its P1-lysogen differ in P1-controlled specificity, but they have the same content of 6-methylaminopurine, and both lack 5-methylcytosine in their DNA. Phage λ contains the same methylated bases as its host of origin, but in reduced amounts and in different proportions. Although minor amounts of these methylated bases may have importance as a result of their location, the presence of the majority of these methylated bases is irrelevant to the specificity of host modification of DNA.
Chromosomal Relocation of Prophage-Associated Bacterial Genes
Authors: Taylor M. W. , Yanofsky C.
Published: January 2020

Taylor
, M. W. (Stanford University, Stanford, Calif.),
and C. Yanofsky
. Chromosomal relocation of prophage-associated bacterial genes. J. Bacteriol.
91:
1469–1476. 1966.—Two distinguishable colony types, rough-edged and smooth-edged, were observed when tryptophan auxotrophs of
Escherichia coli
were transformed to tryptophan independence with DNA from the hybrid nondefective transducing phage i
λ
h
φ80
T
1
S
tryp A
+
B
+
, and with the helper phage λi
434
. P1kc transduction experiments with cells of the two types of colonies as genetic donors showed that the i
λ
h
φ80
T
1
S
tryp A
+
B
+
prophage was located at different regions of the
E. coli
chromosome. In cells of rough-edged colonies, the prophage was linked to the
tryp-cys
region, its normal location, whereas in cells of smooth-edged colonies the prophage was associated with the
gal
region. When transformation experiments were performed with a
T
1
R
tryp
−
deletion mutant as recipient, and phage λi
434
as helper, prophage localization was only detected at the
gal
region. Localization of
λ
h
φ80
T
1
S
tryp A
+
B
+
prophage near
gal
does not appear to be due to the formation of a recombinant phage carrying
tryp
A
+
B
+
, but is due to some type of interaction between the genomes of i
λ
h
φ80
T
1
S
tryp A
+
B
+
and the helper phage. When conditions comparable to those used in transformation studies were employed in transduction experiments, including the use of helper phage, two classes of transductants with either
cys
or
gal
linkage were also observed. To examine whether the location of the prophage on the
E. coli
chromosome had any effect on the ability of the prophage-associated
tryp
A
+
and
tryp
B
+
genes to function or respond to different repression conditions, specific activities of the A and B subunits of tryptophan synthetase specified by the phage genome were measured. Similar values were obtained regardless of the location of the prophage-associated
tryp
genes. Furthermore, the prophage-associated
tryp
genes, free from their normal operator region, permitted enzyme formation which was unaffected by repression or derepression conditions.
Distribution and Function of Genes Concerned with Aromatic Biosynthesis in
Escherichia coli
Authors: Pittard James , Wallace B. J.
Published: January 2020

Pittard, James
(School of Microbiology, University of Melbourne, Victoria, Australia),
and B. J. Wallace
. Distribution and function of genes concerned with aromatic biosynthesis in
Escherichia coli
. J. Bacteriol.
91:
1494–1508. 1966.—A number of mutant strains of
Escherichia coli
K-12, which are blocked in the biosynthesis of the aromatic amino acids, were examined biochemically to determine their particular enzymatic deficiencies. The mutations carried by these strains were mapped by use of the methods of conjugation and transduction. Structural genes for five of the enzymes of the common pathway leading to chorismate and for the two enzymes converting chorismate to phenylpyruvate and
p
-hydroxyphenylpyruvate, respectively, were identified. Unlike the genes of the tryptophan operon most of these genes are distributed over widely separated regions of the chromosome.
Susceptibility and Resistance of Several Fungi to Microbial Lysis
Authors: Potgieter H. J. , Alexander M.
Published: January 2020

Potgieter
, H. J. (Cornell University, Ithaca, N.Y.),
and M. Alexander
. Susceptibility and resistance of several fungi to microbial lysis. J. Bacteriol.
91:
1526–1532. 1966.—Strains of
Streptomyces, Nocardia
, and
Pseudomonas
capable of lysing hyphae of
Fusarium solani
or
Neurospora crassa
were obtained by selective culture, but attempts to isolate an organism lysing
Rhizoctonia solani
failed. When provided with
F. solani
or
N. crassa
as carbon sources, the actinomycetes tested produced β-(1 → 3) glucanase and chitinase. A mixture containing purified chitinase and β-(1 → 3) glucanase induced spheroplast formation in
F. solani
, caused some morphological changes in
N. crassa
, but had almost no effect on
R. solani
hyphae. The polysaccharides in
R. solani
walls, which contain a large amount of glucose as well as galactose, mannose, and glucosamine, were not hydrolyzed appreciably by the two enzymes. Laminaribiose and laminaritriose were released by enzymatic hydrolysis of
F. solani
and
N. crassa
walls, and gentiobiose was liberated from
R. solani
and
N. crassa
walls. Melaninlike materials were found in
R. solani
walls, accounting for 8.50% of the wall weight. A role for melanin in protecting hyphae from microbial lysis is suggested.
Flavin-Linked Dehydrogenation of Ether Glycols by Cell-Free Extracts of a Soil Bacterium
Authors: Payne W. J. , Todd R. L.
Published: January 2020

Payne
, W. J. (University of Georgia, Athens),
and R. L. Todd
. Flavin-linked dehydrogenation of ether glycols by cell-free extracts of a soil bacterium. J. Bacteriol.
91:
1533–1536. 1966.—Cell-free extracts of bacterium TEG-5 grown on tetraethylene glycol dehydrogenated a variety of ether glycols and nonylphenoxy and secondary alcohol ethoxy derivatives. Nicotinamide nucleotides did not serve as electron acceptors, but ferricyanide was effective. Dialysis of crude extract depressed activity with tetraethylene glycol, which was restored then by flavine adenine dinucleotide (FAD) or boiled extract supernatant fluid (BES) but not by other flavins. Precipitatation of extract protein at
p
H 4.0 at 80% ammonium sulfate saturation dissociated FAD and yielded an inactive fraction. Activity was restorable by FAD and BES but not by other flavins. Ethylene glycol was not dehydrogenated by the acid ammonium sulfate fraction with FAD. Atabrine inhibited tetraethylene glycol oxidation, and the inhibition was relieved by FAD but not by other flavins. Tergitols which have sulfated ethoxy side chains on secondary alcohols were not dehydrogenated, but those with free ethoxy side chains on identical alcohols were.
Nonabsorbable Rabbit Anti-
Salmonella typhimurium
Antibody as Detected by the Complement-Mediated Bactericidal Reaction
Authors: Herzberg Mendel , Kenny Kathryn V. , Robbins John B.
Published: January 2020

Herzberg, Mendel
(University of Florida, Gainesville),
Kathryn V. Kenny, and John B. Robbins
. Nonabsorbable rabbit anti-
Salmonella typhimurium
antibody as detected by the complement-mediated bactericidal reaction. J. Bacteriol.
91:
1548–1555. 1966.—A portion of antibody active in the complement-mediated bactericidal reaction against
Salmonella typhimurium
from hyperimmune rabbit serum has been shown to be nonabsorbable by repeated serial absorptions with whole heat-killed or living bacteria. The first two absorptions remove 90 to 95% of the activity, but 1 to 5% cannot be removed by subsequent absorptions. The nonabsorbable antibody appears to be a macroglobulin by density-gradient centrifugation and by comparison of activity and absorbability of purified γ-M and γ-G immune globulins. Alternative hypotheses involving low avidity antibody or antibody to minor cell antigenic components are offered in explanation of the phenomenon.
Control of Aromatic Acid Biosynthesis in
Bacillus subtilis
: Sequential Feedback Inhibition
Authors: Nester E. W. , Jensen R. A.
Published: January 2020

Nester
, E. W. (University of Washington, Seattle),
and R. A. Jensen
. Control of aromatic acid biosynthesis in
Bacillus subtilis
: sequential feedback inhibition. J. Bacteriol.
91:
1594–1598. 1966.—The three major end products of aromatic acid synthesis, tyrosine, phenylalanine, and tryptophan, were tested for their ability to inhibit the first enzymes of the three terminal branches of the pathway as well as the enzyme common to both tyrosine and phenylalanine synthesis. Tyrosine inhibits the activity of prephenate dehydrogenase and also prephenate dehydratase to a limited extent. Phenylalanine inhibits the activity of prephenate dehydratase and, at much higher concentrations, prephenate dehydrogenase. Tryptophan inhibits the activity of anthranilate synthetase and, to some extent, prephenate dehydrogenase and prephenate dehydratase. Chorismate mutase is not inhibited by either 1 m
m
tyrosine or 1 m
m
phenylalanine when these are present singly or together in the reaction mixture. The significance of the feedback control of the terminal branches to the feedback control of that part of the pathway common to the synthesis of all three amino acids is discussed.
Prodigiosin Synthesis in Mutants of
Serratia marcesens
Authors: Morrison D. A.
Published: January 2020

Morrison
, D. A. (Harvard College, Cambridge, Mass.). Prodigiosin synthesis in mutants of
Serratia marcescens
. J. Bacteriol.
91:
1509–1604. 1966.—Exchange of biosynthetic intermediates through the culture medium was used to characterize several hundred new color mutants of
Serratia marcescens
. The general scheme of prodigiosin synthesis as a bifurcated pathway, in which monopyrrole and bipyrrole precursors are synthesized separately and then coupled to form pigment, was confirmed and extended. Mutants of one new class excreted a product likely to be a new intermediate in monopyrrole synthesis, those of a second excreted a new product in the bipyrrole pathway, and those of a third were blocked at early steps in both pathways. Two novel classes of mutants were isolated, in each of which a lack of some product present in
Serratia
and
Escherichia
cultures resulted in loss of all steps in prodigiosin biosynthesis.
Alterations of Protein Synthesis in Arbovirus-Infected L Cells
Authors: Lust George
Published: January 2020

Lust, George
(Fort Detrick, Frederick, Md.). Alterations of protein synthesis in arbovirus-infected L cells. J. Bacteriol.
91:
1612–1617. 1966.—Cellular protein synthesis and ribonucleic acid (RNA) synthesis in mouse L cells were markedly depressed 1 hr after infection with Venezuelan equine encephalomyelitis virus. Host RNA and protein synthesis were inhibited more rapidly by the virus infection than by actinomycin D. In cells infected 4 hr, a cytoplasmic RNA polymerase was demonstrated which was absent in uninfected cells. At this time, deoxyribonucleic acid-directed RNA synthesis catalyzed by the nuclear RNA polymerase was inhibited in vitro in enzyme preparations from nuclei of virus-infected cells. For optimal activity, the cytoplasmic RNA polymerase required the four nucleoside triphosphates, Mg
++
, and RNA. The enzyme was insensitive to actinomycin D and deoxyribonuclease, indicating that it catalyzed RNA-directed RNA synthesis. Attempts to purify the induced polymerase further were unsuccessful. Fresh preparations had to be used because the enzymatic activity was unstable.
Application of Cell Fractionation Techniques in the Study of Cells Infected with Polyoma Virus and Newcastle Disease Virus
Authors: Fisher Harold W. , Matsumiya Hidemi , Azuma Masanobu
Published: January 2020

Fisher, Harold
W. (University of Rhode Island, Kingston),
Hidemi Matsumiya, and Masanobu Azuma
. Application of cell fractionation techniques in the study of cells infected with polyoma virus and Newcastle disease virus. J. Bacteriol.
91:
1645–1651. 1966.—Techniques which permitted rigorous separation of nuclei and cytoplasm were applied to the study of the formation of Newcastle disease virus (NDV) in an established line of Chinese hamster cells and of polyoma virus (PYV) in mouse embryo fibroblasts. The results obtained for hemagglutinin and plaque-forming titers during virus growth were in agreement with those obtained by others, using different techniques. These indicated that NDV matures in the cytoplasm, and PYV in the nucleus, of host cells.
Isolation of Psychrophilic Species of
Bacillus
Authors: Larkin J. M. , Stokes J. L.
Published: January 2020

Larkin
, J. M. (Washington State University, Pullman),
and J. L. Stokes
. Isolation of psychrophilic species of
Bacillus
. J. Bacteriol.
91:
1667–1671. 1966.—Ninety psychrophilic isolates of
Bacillus
were obtained from soil, mud, and water by selective enrichment at 0 C. They grew well at 0 C, optimally at 20 to 25 C, and failed to grow at 30 or 35 C. Their minimal and maximal growth temperatures were lower than those for mesophilic species of
Bacillus
by 10 C or more. Growth of psychrophilic isolates also occurred at −2 and −4.5 C, and both spore formation and spore germination occurred at 0 C.
Heat Stability and Species Range of Purified Staphylococcal α-Toxin
Authors: Cooper Louis Z. , Madoff Morton A. , Weinstein Louis
Published: January 2020

Cooper, Louis
Z. (New England Medical Center Hospital, Boston, Mass.),
Morton A. Madoff, and Louis Weinstein
. Heat stability and species range of purified staphylococcal α-toxin. J. Bacteriol.
91:
1686–1692. 1966.—Heating of high-titer purified staphylococcal α-toxin at 60 and 80 C resulted in a double-sloped curve of inactivation of the hemolytic effect on rabbit erythrocytes. Early inactivation was less at the lower temperature, but activity persisted for a longer time at 80 C. Toxin inactivated at 60 C showed renewed activity when heated briefly at 80 C. A precipitate which formed during heating of α-toxin at 60 or 80 C yielded hemolytic activity when resuspended and heated at 80 but not at 60 C. Supernatant fluid of heat-precipitated toxin was heat-labile and did not regain activity when heated at 80 C. The results indicate that the “paradoxical effect” of heating of staphylococcal α-toxin is not due to a thermolabile inhibitor, but results from alteration of the toxin molecule to a heat-stable active form. Demonstration of renewed activity by 80 C heating of purified toxin requires potent toxin preparations and brief heating periods. Hemolysis of erythrocytes of several animal species by purified α-toxin was generally similar to that produced by impure toxin. Rabbit cells were most susceptible. Human and horse erythrocytes hemolyzed to less than 0.1% of the extent of rabbit cells. Blood cells of other species were intermediate in their response to the lytic effect of α-toxin.
Characterization of “Clearance” Factor and “Cell-bound” Antibody in Experimental Typhoid
Authors: Ushiba Daizo , Nakae Taiji , Akiyama Takehisa , Kishimoto Yoshio
Published: January 2020

Daizo, Ushiba
(Keio University School of Medicine, Tokyo, Japan),
Taiji Nakae, Takehisa Akiyama, and Yoshio Kishimoto
. Characterization of “clearance” factor and “cell-bound” antibody in experimental typhoid. J. Bacteriol.
91:
1705–1712. 1966.—The “clearance” factor produced in the serum of rabbits immunized with a killed vaccine of an S-type virulent strain of
Salmonella enteritidis
was identified as O agglutinin and characterized immunochemically as a class of macroglobulin with a sedimentation coefficient of 12.7
S
. The macroglobulin, which was isolated by means of diethylaminoethyl cellulose column chromatography and sucrose density gradient centrifugation, showed a single protein peak when subjected to cellulose acetate electrophoresis and analytical ultracentrifugation. Its activity as agglutinin and “clearance” factor was inactivated both by mercaptoethanol treatment and absorbtion with the specific O antigen. The H agglutinin was also isolated as a single globulin fraction with relatively low molecular weight, and was characterized as a 7
S
γ-globulin. This fraction had no “clearance” activity. A macroglobulin, similar to that identified in the rabbit serum, was extracted with urea from the cells of mice immunized with the S-type killed vaccine, but not from mice immunized with a live vaccine (R-type mutant), although this latter vaccine is very effective in producing a solid immunity against typhoid disease. The relation of this “cell-bound” antibody to the mechanism of “cellular” immunity in experimental typhoid is discussed.
Laboratory Assays of Different Types of Field Trial Typhoid Vaccines and Relationship to Efficacy in Man
Authors: Pittman Margaret , Bohner Howard J.
Published: January 2020

Pittman, Margaret
(National Institutes of Health, Bethesda, Md.),
and Howard J. Bohner
. Laboratory assays of different types of field trial typhoid vaccines and relationship to efficacy in man. J. Bacteriol.
91:
1713–1723. 1966.—Antibody responses of rabbits to H, O, and Vi antigens did not differentiate vaccine K (acetone-killed and dried) from vaccine L (heat-phenolized and dried) relative to human efficacy. A mouse protection assay in which intraperitoneal vaccination and challenge suspended in mucin were used showed vaccine K to be 3.69 times more potent than vaccine L; with subcutaneous vaccination, vaccine K was only 0.78 as potent. With the challenge suspended in saline, the effect of the route of vaccination was accentuated. An old U.S. reference vaccine, heat-phenolized, induced the same types of response as vaccine L. In the assay with intraperitoneal vaccination and mucin-suspended challenge, the potency of vaccine K relative to vaccine L and the potencies of Polish vaccines, P, N, and T, relative to vaccine K were directly correlated with the efficacies of the vaccines for man, as reported for the recent World Health Organization cooperative field trials in British Guiana, Yugoslavia, and Poland. This assay gave a high potency for alcohol-treated vaccine V relative to vaccine L, but the values did not reflect relative efficacy in the USSR field trial; the subcutaneous vaccination assay more closely reflected their human efficacy. An analysis suggested that vaccine K had a mouse protective factor not present in vaccine L and that vaccine V may have had a third factor. The influence of a few variable factors on the assay with intraperitoneal vaccination and mucin-suspended challenge was studied briefly.
Growth, Morphogenesis, and Virulence of
Candida albicans
after Oral Inoculation in the Germ-Free and Conventional Chick
Authors: Balish Edward , Phillips A. W.
Published: January 2020

Balish, Edward
(Syracuse University, Syracuse, N.Y.),
and A. W. Phillips
. Growth, morphogenesis, and virulence of
Candida albicans
after oral inoculation in the germ-free and conventional chick. J. Bacteriol.
91:
1736–1743. 1966.—The effects of intestinal bacteria on the multiplication, morphogenesis, and infectivity of
Candida albicans
in the alimentary tract were investigated by comparing results obtained in germ-free and conventional chicks after oral inoculation. This challenge resulted in the establishment of large numbers of the pathogen in the alimentary tract of each group of chicks; these numbers were increased in crop contents from challenged bacteria-free chicks wherein hyphae predominated over the yeast form. These animals also had lesions of the crop epithelium containing numerous hyphae and few yeast-like forms. In contrast, challenged conventional chicks receiving an adequate diet displayed no evidence of infection. Their alimentary tract contained the yeast form of
C. albicans
; no hyphae were seen. Although we found bacterial inhibition of
C. albicans
multiplication in the alimentary tract, this in itself did not seem to explain the resistance to intestinal candidiasis in our conventional chicks. We argued that this resistance to infection was due chiefly to the prevention of hyphal development in
C. albicans
by intestinal bacteria.
C. albicans
in the gut of our conventional chicks resulted in some increase in numbers of enterococci in contents from the crop. Increased
p
H values in contents from the gut of germ-free chicks were not clearly related to infection after challenge. The
E
h
of the above crop contents were only slightly decreased in the germ-free crop. Thus the
E
h
did not appear to be involved in susceptibility to infection. Invasion of the blood stream and kidneys of conventional chicks by the yeast form of
C. albicans
occurred in challenged animals receiving a purified diet which had been radiation-sterilized and stored for 6 months at room temperature (25 C). Their growth rate decreased and they became moribund; no hyphae were observed in tissues or intestine of these animals. Challenged bacteria-free chicks receiving the same diet were resistant to the above invasion, although they had crop lesions containing hyphae as described. The resistance of these chicks to systemic invasion was attributed to absence of intestinal bacteria competing for low levels of vitamins in the stored diet. Germ-free chicks had decreased levels of serum γ-globulin which increased after challenge, whereas this value was unchanged in conventional birds after challenge.
Growth and Virulence of
Candida albicans
after Oral Inoculation in the Chick with a Monoflora of Either
Escherichia coli
or
Streptococcus faecalis
Authors: Balish Edward , Phillips A. W.
Published: January 2020

Balish, Edward
(Syracuse University, Syracuse, N.Y.),
and A. W. Phillips
. Growth and virulence of
Candida albicans
after oral inoculation in the chick with a monoflora of either
Escherichia coli
or
Streptococcus faecalis
. J. Bacteriol.
91:
1744–1749. 1966.—Bacterial protection against intestinal infection by
Candida albicans
was investigated in chicks with a monoflora of either
Escherichia coli
or
Streptococcus faecalis
. These animals were obtained by orally inoculating germ-free chicks (3 days old) with pure cultures of bacteria. Each bacterial species was established in large numbers in the gut of separate groups of animals within 24 hr of inoculation; these numbers were similar in chicks examined 34 days later, at which time all animals were killed. The numbers of bacteria from contents of the crop, small intestine, and ceca were similar in chicks with the
E. coli
monoflora. Comparable results were obtained in chicks with the
S. faecalis
monoflora, except for decreased numbers in the duodenum and jejunum. Some of the monoflora chicks (7 days old) were transferred into separate isolators, orally inoculated with
C. albicans
, and observed for 34 days. All chicks grew well and appeared healthy. However, examinations at autopsy revealed severe crop infections in chicks with a diflora containing
S. faecalis
. Preferential growth of hyphae (
C. albicans
) occurred in the lesions and throughout the gut. The numbers of
S. faecalis
in the gut were comparable to those found in unchallenged animals. Agglutinins against
C. albicans
were not detected in our test or control chicks. Chicks with a diflora containing
E. coli
and
C. albicans
had a few microscopic crop lesions containing small numbers of hyphae.
C. albicans
was well established in the gut of these animals, largely as the yeast form. The numbers of
E. coli
in the gut were similar to those in control chicks. Thus, it was concluded that
E. coli
provided protection against crop infection by
C. albicans
. In crop contents from unchallenged animals, chicks with
S. faecalis
monoflora were about
p
H 5, whereas birds with
E. coli
monoflora were about
p
H 7. The challenge did not greatly change the former value, and the latter was slightly decreased. In the crop of unchallenged birds, negative
E
h
values were found in chicks with
S. faecalis
and positive
E
h
values in those with
E. coli
. Challenge did not greatly change these values. These data on
p
H and
E
h
were related to conditions for morphogenesis of
C. albicans
and virulence. No major difference in the concentrations of serum proteins was seen in chicks with
E. coli
or
S. faecalis
after challenge with
C. albicans
. Possible mechanisms of the protective effect of
E. coli
are discussed.