bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification by antibody to a synthetic peptide of a protein specified by a diploid gene located in the terminal repeats of the L component of herpes simplex virus genome
Authors: Ackermann M , Chou J , Sarmiento M , Lerner R A , Roizman B
Published: January 2020

In the course of studies on the a sequences located at the termini of and at the junction between the L and S components of herpes simplex virus 1 DNA, J. Chou and B. Roizman (J. Virol. 57:629-637, 1986) noted that the a sequence acted as a gamma 1 promoter when fused to the structural sequence of the thymidine kinase gene, the b inverted repeat sequences located in the L component next to the a sequences contained an open reading frame predicted to encode the protein of 358 amino acids with a molecular weight of 37,054, and the transcription of an RNA homologous to the open reading frame initiated within the a sequence. The nucleotide sequence of the open reading frame predicted the presence of the triplet Ala-Thr-Pro repeated 10 times. To verify the existence of the predicted gene, designated gamma 134.5, a synthetic peptide consisting of the triplet Ala-Thr-Pro repeated 10 times was synthesized and used to raise antibodies in rabbits. The results were as follows. The antiserum to the peptide reacted with a 43,500-apparent-molecular-weight protein present in lysates of cells infected with herpes simplex virus 1 but not present in mock-infected or herpes simplex virus 2-infected cells. We genetically engineered a recombinant virus containing a single copy of a truncated gene. Concordant with predictions, the antibody reacted with a faster-migrating protein in cells infected with this recombinant. The gamma 134.5 gene product was soluble, and it accumulated primarily in the cytoplasm late in infection. The overlap of the domain of the gamma 134.5 gene with the a sequence raises the possibility that it acts in trans on the a sequence and is associated with one of the functions currently ascribed to the a sequences.
Mapping regions of the matrix protein of vesicular stomatitis virus which bind to ribonucleocapsids, liposomes, and monoclonal antibodies
Authors: Ogden J R , Pal R , Wagner R R
Published: January 2020

The matrix (M) protein of vesicular stomatitis virus (VSV) appears to function as a bridge between the ribonucleocapsid (RNP) core and the envelope in assembly of the virion. Two such properties would necessitate at least one site for interaction with the nucleocapsid and one with the envelope. In this study M protein was found to mediate the in vitro binding to RNP cores of phospholipid vesicles, representing membrane structures. The M protein could bind initially to either the vesicles or the RNP cores to promote RNP-vesicle association. A trypsin-resistant fragment (MT) of M protein, missing the initial 43 amino acids from its amino terminus, reconstituted with acidic phospholipid vesicles with the same binding efficiency as did whole M protein, suggesting that the carboxy-terminal 81% retained those regions of the M protein which interact with a lipid bilayer. The MT protein, however, was considerably less efficient than intact M protein as an inhibitor of in vitro virus transcription; almost 2.5-fold more MT protein than intact M protein was required for 50% inhibition of VSV transcription, indicating that a site for interaction with the RNP core may have been lost. A monoclonal antibody which is able to reverse the in vitro inhibition of transcription by M protein did not react by immunoblotting with MT protein. Partial tryptic digests of the M protein probed with this monoclonal antibody indicated that epitope 1 lies between amino acid residues 18 and 43. This region appears to be a site that promotes interaction of the M protein with the RNP core of VSV. Monoclonal antibodies to epitopes 2 and 3, which exhibit some overlap in binding to M protein but do not reverse transcription inhibition, were mapped by cleavage with N-chlorosuccinimide at regions in a carboxy direction from epitope 1.
Intracellular assembly and packaging of hepatitis B surface antigen particles occur in the endoplasmic reticulum
Authors: Patzer E J , Nakamura G R , Simonsen C C , Levinson A D , Brands R
Published: January 2020

Hepatitis B surface antigen (HBsAg) particles are secreted by Chinese hamster ovary cells that are stably transfected with the S gene of hepatitis B virus. The assembly of HBsAg into cylindrical and spherical particles occurred intracellularly within the endoplasmic reticulum. HBsAg particles accumulated within large dilated areas of the endoplasmic reticulum and remained within these structures for most of the time prior to secretion from the cells. Once the particles were formed, the HBsAg polypeptides did not appear to become associated with subsequent intracellular organelle membranes or the plasma membrane. HBsAg within the dilated structures did not bind wheat germ agglutinin, indicating that its oligosaccharide chains had not yet been processed to the complex form (containing terminal sialic acid-N-acetylglucosamine residues). The oligosaccharide chains of HBsAg are processed to the complex form and can be detected on the HBsAg after secretion, but this event was not detected within cells. In addition, HBsAg was not observed on the cell surface by indirect immunofluorescence or immunoprecipitation, although immunoelectron microscopy revealed some staining at or near the cell surface. These results suggested that HBsAg was either secreted from cells without being incorporated into the plasma membrane, or that the levels of HBsAg in the plasma membrane were below the limits of detection.
Cloning of monomeric human papillomavirus type 16 DNA integrated within cell DNA from a cervical carcinoma
Authors: Matsukura T , Kanda T , Furuno A , Yoshikawa H , Kawana T , Yoshiike K
Published: January 2020

We have molecularly cloned and characterized monomeric human papillomavirus type 16 DNA with flanking cell DNA sequences from a cervical carcinoma. Determination of nucleotide sequence around the junctions of human papillomavirus and cell DNAs revealed that at the site of integration within cell DNA the cloned viral DNA had a deletion between nucleotides 1,284 and 4,471 (numbering system from K. Seedorf, G. Krämmer, M. Dürst, S. Suhai, and W. G. Röwekamp, Virology 145:181-185, 1985), which includes the greater part of E1 gene and the entire E2 gene. In the remaining part of the E1 gene, three guanines were found at the location where two guanines at nucleotides 1,137 and 1,138 have been recorded. This additional guanine shifted the reading frame and erased an interruption in the E1 gene described by Seedorf et al. The data strongly suggest that, like other papillomaviruses, human papillomavirus type 16 has an uninterrupted E1 gene.
Bacteriocinlike killing action of a temperate bacteriophage phiBA1 of Bacillus aneurinolyticus
Authors: Ito S , Nishimune T , Abe M , Kimoto M , Hayashi R
Published: January 2020

A new temperate phage, phiBA1, was isolated from Bacillus aneurinolyticus, phiBA1 had an icosahedral head with a diameter of about 70 nm and a tail about 20 nm long and contained a circularly permuted, linear duplex DNA of about 38 x 106 daltons. This phage showed two activities: bacteriocin-like killing activity against five strains of B. aneurinolyticus and normal temperate phage activity against three other strains. phiBA1 killed sensitive cells by a single-hit process. After adsorption of phiBA1 to cells sensitive to killing, the content of intracellular ATP increased for the first 5 min and then gradually decreased. Phage DNA injected into the cell immediately after infection was degraded rapidly. Killing was also caused by heavily UV-irradiated phiBA1. Killing-resistant mutants showed normal adsorption of phiBA1 and normal injection of the DNA with its instantaneous restriction. Our results indicate that the killing action of phiBA1 is different from the phenomenon of abortive infection and suggest that the killing might be caused by a proteinaceous component of phiBA1.
Protective effect of monoclonal antibodies on lethal mouse hepatitis virus infection in mice
Authors: Nakanaga K , Yamanouchi K , Fujiwara K
Published: January 2020

Neutralizing and nonneutralizing monoclonal antibodies to the peplomer glycoprotein and nucleocapsid protein of a mouse hepatitis virus (MHV), MHV-NuU, protected mice against lethal MHV-2 challenge. Histopathologically, livers of mice receiving protective antibodies showed some focal necrotic lesions with remarkable cellular infiltration instead of fulminant hepatitis caused by MHV-2.
DNA sequence of the gene for pseudorabies virus gp50, a glycoprotein without N-linked glycosylation
Authors: Petrovskis E A , Timmins J G , Armentrout M A , Marchioli C C , Yancey R J , Post L E
Published: January 2020

The DNA sequence was determined for a region of the pseudorabies virus (PRV) genome to which a mutation defining resistance to a monoclonal antibody has been mapped (M. W. Wathen and L. M. K. Wathen, J. Virol., 51:57-62, 1984). This sequence was found to contain an open reading frame that did not include an amino acid sequence directing N-linked glycosylation. This open reading frame was expressed in uninfected Chinese hamster ovary cells to produce the PRV glycoprotein gp50. When PRV-infected Vero cells were incubated in the presence of tunicamycin, the gp50 that was produced had an identical molecular weight to that produced in the absence of drug. When infected cells were incubated in the presence of monensin, the molecular weight of gp50 was reduced from 60,000 to 45,000, but was not sensitive to endo-beta-N-acetylglucosaminidase H. These observations led to the conclusion that gp50 does not contain N-linked carbohydrate, as predicted from the DNA sequence. A region of the amino acid sequence and the positions of the cysteine residues of PRV gp50 are homologous to glycoprotein D of herpes simplex virus.
Synthesis and processing of bovine herpesvirus 1 glycoproteins
Authors: van Drunen Littel-van den Hurk S , Babiuk L A
Published: January 2020

Four unique glycoproteins or glycoprotein complexes were recognized by a panel of monoclonal antibodies to bovine herpesvirus 1 (BHV-1), i.e., GVP 6/11a/16 (130,000-molecular-weight glycoprotein [130K glycoprotein]/74K/55K), GVP 7 (108K), GVP 3/9 (180K/91K), and GVP 11b (71K). The absence of any antigenic or structural relationship between GVP 11a and GVP 11b, which were previously identified as one glycoprotein, GVP 11, demonstrated that these two GVP 11 species are unique glycoproteins. GVP 3 and GVP 9 showed complete sequence homology, as shown by the identity of their antigenic determinants and by partial peptide mapping. This observation, as well as the ratio of their apparent molecular weights, indicated that GVP 3 (180K) is a dimeric form of GVP 9 (91K). GVP 6 and GVP 11a, as well as GVP 6 and GVP 16, showed at least partial sequence homology, since they shared several antigenic determinants and peptides. In addition, GVP 6, GVP 11a, and GVP 16 were derived from one primary precursor. These results, as well as the ratio of their apparent molecular weights, indicated that the GVP 6/11a/16 complex consists of two forms: one in which GVP 6 (130K) is uncleaved and the other one in which GVP 6 is cleaved and composed of GVP 11a (74K) and GVP 16 (55K), linked by disulfide bridges. An antigenically distinct precursor to each of the four BHV-1 glycoproteins or glycoprotein complexes was identified by monoclonal antibodies. These precursors, pGVP 6 (117K), pGVP 11a (62K), pGVP 7 (100K), pGVP 9 (69K), and pGVP 11b (63K) were sensitive to endo-beta-N-acetylglucosaminidase H treatment, indicating that they represent the partially glycosylated high-mannose-type intermediate forms generated by cotranslational glycosylation of the primary, unglycosylated precursors to GVP 6/11a/16, GVP 7, GVP 3/9, and GVP 11b, which were identified as having apparent molecular weights of 105,000, 90,000, 61,000, and 58,000, respectively. A new nomenclature for the BHV-1 glycoproteins, based on roman numerals, is proposed.
Molecular characterization of Marek's disease herpesvirus B antigen
Authors: Isfort R J , Sithole I , Kung H J , Velicer L F
Published: January 2020

The Marek's disease herpesvirus (MDHV) B antigen (MDHV-B) was identified and molecularly characterized as a set of three glycoproteins of 100,000, 60,000, and 49,000 apparent molecular weight (gp100, gp60, and gp49, respectively) by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) after immunoprecipitation from [35S]methionine-labeled infected cells by specific rabbit antiserum directed against MDHV-B (R alpha B), as previously determined by immunodiffusion. Further identification was accomplished by blocking this immunoprecipitation with highly purified MDHV-B. The same set of three polypeptides was also immunoprecipitated from [35S]methionine- and 14C-labeled infected cells with two other sera shown to have anti-B activity, i.e., rabbit anti-MDHV-infected-cell plasma membrane (R alpha PM) and immune chicken serum from birds naturally infected with MDHV. The three herpesvirus of turkeys (HVT) B-antigen (HVT-B) glycoproteins immunoprecipitated with all three sera containing anti-B activity were also shown to be identical in size to those of MDHV-B by immunoprecipitation and SDS-PAGE. These data serve to clarify the molecular identification of the polypeptides found in common between MDHV and HVT by linking them to MDHV-B, previously identified only by immunodiffusion, and to a similarly sized set of immunologically related common glycoproteins called gp100, gp60, and gp49, detected with monoclonal antibody by other workers. Tunicamycin inhibition of N-linked glycosylation resulted in either nonglycosylated or O-linked glycosylated putative precursors of MDHV-B and HVT-B with apparent molecular weights of 88,000, called pr88, and 44,000, tentatively called pr44, both immunoprecipitable with all three sera. However, the relationships of these two polypeptides to each other and to the overall precursor-processing relationship of the MDHV-B complex remains to be elucidated. The three fully glycosylated B-antigen polypeptides were not connected by disulfide linkage. Collectively, the data presented here and by others support the conclusion that all three glycoproteins now identified as gp100, gp60, and gp49 have MDHV-B determinants. Finally, detection of the same three polypeptides with well-absorbed R alpha PM, which was directed against purified infected-cell plasma membranes, suggests that at least one component of the B-antigen complex has a plasma membrane location in the infected cell.(ABSTRACT TRUNCATED AT 400 WORDS)
Transformation of T-lymphoid cells by Abelson murine leukemia virus
Authors: Scott M L , Davis M M , Feinberg M B
Published: January 2020

Abelson leukemia virus (A-MuLV) is an oncogenic murine retrovirus whose genome contains sequences homologous to those of a normal cellular gene, c-abl. It has been demonstrated to cause rapid transformation of several cell types, including pre-B lymphocytes, macrophages, and fibroblasts. More recently, A-MuLV has been reported to induce thymic tumors in a mouse strain (C57BL/Ka) previously thought to be resistant to disease induction. We showed that the masses occurring after intrathymic injection of the virus were composed of lymphocytes of a previously described immature T-cell phenotype. This phenotype has been defined here by flow cytometry of 10 primary tumor samples stained with antibodies to several thymocyte differentiation antigens. Hybridization of DNAs from these tumors with v-abl, immunoglobulin mu, and T-cell antigen receptor beta-chain probes confirmed the T-lymphoid, polyclonal nature of the primary tumor cells. The primary tumors were malignant, as clearly shown by reinjection into Thy-congenic host animals. Further, four Thy- in vitro cell lines derived from three tumors differed from the majority of primary tumor cells and were similar to previously described A-MuLV-transformed pre-B cells. The consistent T-lymphoid phenotype exhibited by primary A-MuLV thymomas may represent one stage of normal thymocyte differentiation.
Expression of defective measles virus genes in brain tissues of patients with subacute sclerosing panencephalitis
Authors: Baczko K , Liebert U G , Billeter M , Cattaneo R , Budka H , ter Meulen V
Published: January 2020

The persistence of measles virus in selected areas of the brains of four patients with subacute sclerosing panencephalitis (SSPE) was characterized by immunohistological and biochemical techniques. The five measles virus structural proteins were never simultaneously detectable in any of the brain sections. Nucleocapsid proteins and phosphoproteins were found in every diseased brain area, whereas hemagglutinin protein was detected in two cases, fusion protein was detected in three cases, and matrix protein was detected in only one case. Also, it could be shown that the amounts of measles virus RNA in the brains differed from patient to patient and in the different regions investigated. In all patients, plus-strand RNAs specific for these five viral genes could be detected. However, the amounts of fusion and hemagglutinin mRNAs were low compared with the amounts in lytically infected cells. The presence of particular measles virus RNAs in SSPE-infected brains did not always correlate with mRNA activity. In in vitro translations, the matrix protein was produced in only one case, and the hemagglutinin protein was produced in none. These results indicate that measles virus persistence in SSPE is correlated with different defects of several genes which probably prevent assembly of viral particles in SSPE-infected brain tissue.
Amino-terminal mutation of the vesicular stomatitis virus glycoprotein does not affect its fusion activity
Authors: Woodgett C , Rose J K
Published: January 2020

Earlier studies demonstrated that synthetic peptides corresponding to the amino terminus of the vesicular stomatitis virus glycoprotein (G protein) have a pH-dependent hemolytic activity that is thought to be related to the fusion activity of G protein (R. Schlegel and M. Wade, J. Biol. Chem. 259: 4691-4694, 1984; R. Schlegel and M. Wade, J. Virol. 53: 319-323, 1985). A single amino acid change (lysine to glutamic acid at the amino terminus) abolishes the hemolytic activity of the peptide. Here we used oligonucleotide-directed mutagenesis to create a DNA encoding G protein with this same amino acid change at its amino terminus. The mutant protein encoded by this gene was expressed transiently in a monkey fibroblast cell line (COS) and was found to have a pH-dependent fusion activity indistinguishable from wild-type G protein. This result indicates that the hemolytic activity of the synthetic peptides was not related to the fusion activity of the G protein.
Interferon response in normal and Aleutian disease virus-infected mink
Authors: Wiedbrauk D L , Hadlow W J , Ewalt L C , Lodmell D L
Published: January 2020

Studies were done to determine whether differences in interferon production are responsible for the resistance of pastel mink to Aleutian disease. The abilities of normal pastel and sapphire mink to produce interferon when inoculated with either Newcastle disease virus or a synthetic polyribonucleotide, poly (I):poly (C), were identical, even to the production of a novel, acid-labile interferon. The resistance of pastel mink to Aleutian disease did not correlate with interferon production, because neither sapphire nor pastel mink produced detectable amounts of interferon when infected with either the Pullman strain of Aleutian disease virus (ADV) or the highly virulent Utah I strain. Sapphire mink infected with the Pullman strain responded normally to poly (I):poly (C) early in the course of the disease, but interferon production was impaired late, when the mink were hypergammaglobulinemic and had renal, vascular, and hepatic lesions. These data suggest that ADV Pullman neither stimulates nor interferes with interferon production in infected mink and may represent a mechanism whereby ADV can more readily establish infection.
Sequential detection of different antigens induced by Epstein-Barr virus and herpes simplex virus in the same Western blot by using dual antibody probes
Authors: Lin J C , Pagano J S
Published: January 2020

A dual antibody probing technique that permitted a color-coded identification of polypeptides representing different classes of Epstein-Barr virus (EBV) antigens as well as differentiation of the polypeptides induced by different herpesviruses in the same Western blot was developed. When the nitrocellulose sheet was probed first with monoclonal antibody against EBV early antigen diffuse component (EA-D) and then stained with 4-chloro-1-naphthol, four polypeptides specific for EA-D were identified by purple bands. Subsequently, the same nitrocellulose sheet was reprobed with human serum containing antibodies against EBV early antigen, viral capsid antigen, and nuclear antigen and stained with 3,3'-diaminobenzidine. Several brown bands corresponding to early, viral capsid, and nuclear antigen polypeptides were detected. The dual antibody probing technique was used in an analysis to differentiate polypeptides resulting from either EBV or herpes simplex virus infection, either in cells infected by individual virus or in a cell line dually infected by both viruses. On the basis of different colored bands in different lanes of the same gel, 20 polypeptides with molecular weights ranging from 31,000 to 165,000 were identified as herpes simplex virus-specific proteins. These results suggested that the dual antibody probing technique may be applicable in clinical diagnosis for detecting antigens and antibodies derived from different pathogens.
Transduction of c-src coding and intron sequences by a transformation-defective deletion mutant of Rous sarcoma virus
Authors: Soong M M , Iijima S , Wang L H
Published: January 2020

The mechanism of cellular src (c-src) transduction by a transformation-defective deletion mutant, td109, of Rous sarcoma virus was studied by sequence analysis of the recombinational junctions in three td109-derived recovered sarcoma viruses (rASVs). Our results show that two rASVs have been generated by recombination between td109 and c-src at the region between exons 1 and 2 defined previously. Significant homology between td109 and c-src sequences was present at the sites of recombination. The viral and c-src sequence junction of the third rASV was formed by splicing a cryptic donor site at the 5' region of env of td109 to exon 1 of c-src. Various lengths of c-src internal intron 1 sequences were incorporated into all three rASV genomes, which resulted from activation of potential splice donor and acceptor sites. The incorporated intron 1 sequences were absent in the c-src mRNA, excluding its being the precursor for recombination with td109 and implying that initial recombinations most likely took place at the DNA level. A potential splice acceptor site within the incorporated intron 1 sequences in two rASVs was activated and was used for the src mRNA synthesis in infected cells. The normal env mRNA splice acceptor site was used for src mRNA synthesis for the third rASV.
Immunological comparison of scrapie-associated fibrils isolated from animals infected with four different scrapie strains
Authors: Kascsak R J , Rubenstein R , Merz P A , Carp R I , Robakis N K , Wisniewski H M , Diringer H
Published: January 2020

Scrapie-associated fibrils (SAFs) are abnormal filamentous structures that are uniquely associated with unconventional slow virus diseases. The antigenic relationships of SAFs from animals infected with four biologically distinct scrapie strains were investigated by using antisera raised to purified SAF proteins. Rabbit antisera were raised to SAFs isolated from mice infected with the ME7 scrapie strain and to SAFs isolated from hamsters infected with the 263K scrapie strain. A strong antigenic relationship was shown among SAF proteins (PrPs) isolated from all scrapie-infected animals (ME7, 139A, and 87V in mice and 263K in hamsters), and this relationship was demonstrable regardless of which antiserum was used. SAF proteins were antigenically distinct from those of paired helical filaments or amyloid isolated from patients with Alzheimer disease. Distinct Western blot profiles were demonstrated for SAFs isolated from animals infected with each scrapie strain. Differences seen among SAFs were independent, at least in part, of host species or genotype, implying that certain specific structural and molecular properties of SAFs are mediated by the strain of scrapie agent.
Cellular proteins which can specifically associate with simian virus 40 small t antigen
Authors: Murphy C I , Bikel I , Livingston D M
Published: January 2020

When crude, radiolabeled extracts of various cells were applied to homogeneous simian virus 40 small t antigen-Sepharose adsorbents, three cell proteins (57, 32, and 20 kilodaltons [kDa]) bound specifically. Each also bound to an insoluble, truncated t derivative composed of the COOH-terminal 123 residues of the protein. The binding of these proteins was greatly inhibited after reduction and alkylation of the t ligand. Therefore, some element of native conformation, but not all of the primary structure of t, is necessary for this binding property, which may constitute a discrete, in vitro biochemical function of this protein. Results of cell fractionation experiments suggested that the 57- and 32-kDa proteins are nonnuclear cell constituents, whereas the 20-kDa protein was closely associated with a detergent-washed nuclear fraction. Specific immunoblotting and comparative partial proteolytic digestion analyses indicated that the 57-kDa protein is tubulin, a major component of the cytoskeleton. In this regard, t and tubulin were observed to coimmunoprecipitate from crude cell extracts after incubation with monospecific anti-t antibody. Therefore, it is possible that t and tubulin interact in vivo.
Antibody to mouse alpha/beta interferon abrogates Pichinde virus-induced liver lesions in suckling mice
Authors: Clark T , Gresser I , Pfau C , Moss J , Woodrow D
Published: January 2020

Infection of newborn C3HeB/FeJ mice with the arenavirus Pichinde resulted in stunted growth, severe liver cell degeneration, and death. Administration of sheep anti-mouse alpha/beta interferon globulin completely abrogated liver lesions in virus-infected mice, although it did not decrease the incidence of mortality. These results indicate that endogenous interferon may be responsible for some manifestations of viral disease.
Large T antigens of simian virus 40 and polyomavirus efficiently establish primary fibroblasts
Authors: Jat P S , Sharp P A
Published: January 2020

Recombinant retroviruses that transduce the simian virus 40 (SV40) large T antigen or the polyomavirus large T antigen as well as encoding resistance to antibiotic G418 were used to investigate whether these genes alone were sufficient for immortalization of primary cells. The results provided definitive evidence that either viral gene can efficiently establish primary fibroblasts. The capability of the SV40 large T antigen to establish primary fibroblasts was undiminished by a mutation that alters its binding to sequences within the origin of replication. Surprisingly, most of the primary cells established by the expression of the SV40 large T antigen did not have a transformed phenotype. This suggests that transformation by SV40 is not simply due to a high level of expression of the SV40 large T antigen and stabilization of cellular p53.
Site of attachment of encephalomyocarditis virus on human erythrocytes
Authors: Allaway G P , Burness A T
Published: January 2020

Previous studies of the attachment of encephalomyocarditis (EMC) virus to human erythrocytes concluded that the glycophorins, a family of human erythrocyte sialoglycoproteins, act as EMC virus receptors. Evidence is presented that the major glycophorin species, glycophorin A, is the receptor for EMC virus attachment to human erythrocytes. Comparison of the structures of glycophorins A and B and sialoglycopeptides released by chymotrypsin and trypsin treatment of erythrocytes confirmed our previous suggestion (A. T. H. Burness and I. U. Pardoe, J. Gen. Virol. 64:1137-1148, 1983) that attachment of EMC virus to glycophorin A involves the region containing amino acids 35 to approximately 70 (numbered from the NH2 terminus), four of which (amino acids 37, 44, 47, and 50) are glycosylated. In addition, we provide evidence that the segment containing amino acids 35 to 39 with an oligosaccharide side chain on threonine-37 is particularly important for EMC virus attachment.
Transcription In Vitro by Reovirus-Associated Ribonucleic Acid-Dependent Polymerase
Authors: Banerjee A. K. , Shatkin A. J.
Published: January 2020

Digestion of purified reovirus type 3 with chymotrypsin degrades 70% of the viral protein and converts the virions to subviral particles (SVP). The SVP contain 3 of the 6 viral structural proteins and all 10 double-stranded ribonucleic acid (RNA) genome segments but not adenine-rich, single-stranded RNA. An RNA polymerase which is structurally associated with SVP transcribes one strand of each genome segment by a conservative mechanism in vitro. The single-stranded products include large (1.2 × 10
6
daltons), medium (0.7 × 10
6
daltons), and small (0.4 × 10
6
daltons) molecules which hybridize exclusively with the corresponding genome segments. The enzyme obtained by heating virions at 60 C synthesizes similar products. Kinetic and pulse-chase studies indicate that the different-sized products are synthesized simultaneously but at rates which are in the order: small > medium > large.
Structure and Cytopathic Effects of Nelson Bay Virus
Authors: Gard Geoff , Compans Richard W.
Published: January 2020

A virus isolated from a flying fox (
Pteropus poliocephalus
) has a morphology similar to that of reoviruses. However, unlike the reoviruses, this virus has a rapid cytopathic effect, causing cell fusion, vacuolization of the cytoplasm, and an unusual nuclear degeneration. Immunofluorescence indicates that viral antigen is distributed through both nucleus and cytoplasm. Viral maturation appears to take place in discrete cytoplasmic factories, and there is no apparent involvement of spindle tubules.
Method for Increasing the Regularity of Isolation of Infectious Ribonucleic Acid from Influenza Virus
Authors: Chetverikova L. K. , Polyak R. Y. , Yukhnova L. G. , Smorodintsev A. A.
Published: January 2020

A more effective method of isolating infectious ribonucleic acid (RNA) from influenza virus was evaluated based on the enzymatic disintegration of the viral coat by Pronase, followed by phenol-detergent extraction of the RNA from susceptible and from resistant cells.
Continuous Requirement for Host P10 Protein During Bacteriophage T4 Infection
Authors: Cafferata Robert L. , Haselkorn Robert
Published: January 2020

The
Escherichia coli
30
S
ribosomal protein P10, the product of the
str
gene, known to be involved only in the initiation of protein syntehsis, is required for all bacteriophage T4 protein synthesis.
Intracellular Development of Bacteriophage φR
Authors: Burton Alice J.
Published: January 2020

When
Escherichia coli
is infected with bacteriophage φR, parental deoxyribonucleic acid (the single- or double-stranded DNA containing the isotopic label of the infecting phage) becomes firmly attached to a cellular structure and can be isolated as a rapidly sedimenting component as described earlier for φX174. If this component is centrifuged to equilibrium, two peaks of infective DNA are observed at densities of 1.30 and 1.15 g/ml. At low multiplicities of infection,
32
P-labeled parental DNA is found associated with only the cellular components in the dense band; as the multiplicities of infection are increased, the dense band becomes saturated and parental DNA molecules are then found at the light density as well. Actively replicating host DNA is found only in the dense band, whereas progeny DNA, which does not replicate semiconservatively, can become associated with cellular components in the light band. This fractionation of cellular components on the basis of their buoyant density separates primary sites of DNA replication associated with the dense band from nonfunctional binding sites in the light band.
Susceptibility of Human Cell Strains to Transformation by Simian Virus 40 and Simian Virus 40 Deoxyribonucleic Acid
Authors: Aaronson Stuart A.
Published: January 2020

Marked differences were found in the susceptibility of human fibroblasts to transformation by simian virus 40 (SV40). Highly susceptible cell strains were derived from patients with diseases associated with chromosomal abnormalities and a high incidence of tumors. In the present study, SV40 transformation-susceptible cell strains were not found to have a generalized increase in viral sensitivity. The differences in transformation frequency among cell strains with whole virus are eliminated by the use of isolated SV40 deoxyribonucleic acid, suggesting that the relative resistance of most cell strains to transformation by whole virus is due to a block at an early step in infection.
Isolation of Hemagglutinin and Neuraminidase Subunits of Hemagglutinating Virus of Japan
Authors: Maeno Koichiro , Yoshida Tetsuya , Iinuma Masao , Nagai Yoshiyuki , Matsumoto Toshisada , Asai Junpei
Published: January 2020

When purified hemagglutinating virus of Japan (HVJ) was treated with trypsin, two major surface antigens were released from the virus. The “hemagglutinin” subunits obtained by this method were reactive with homologous hemagglutination-inhibition antibody and could be detected by an antibody-blocking test. They adsorbed to but did not agglutinate red cells and thus appeared to be “monovalent.” The neuraminidase subunits were obtained in fully active form and did not adsorb to red cells. This finding suggests that these two activities of HVJ are associated with different subunits of the virus particle. The hemagglutinin and neuraminidase subunits could be partially separated by zonal rate centrifugation or gel filtration on Sephadex G-200. The molecular weights estimated for these subunits were approximately 124,000 and 114,000, respectively. After treatment with trypsin, virus-associated hemagglutinin and neuraminidase activities were both reduced significantly. The electron micrographs of such trypsinized virus particles showed complete or partial loss of surface projections. These results suggested that the subunits obtained by this method seemed to be those projections liberated from the virus by the action of trypsin.
Characterization of T-Even Bacteriophage Substructures
Authors: Cummings Donald J. , Chapman V. A. , DeLong S. S. , Kusy A. R. , Stone K. R.
Published: January 2020

Tail plates obtained from T4D amber mutants were examined with respect to sedimentation behavior, subunit molecular weights, amino acid composition, isoelectric points, and morphology. Intact plates had an
S
20,w
of 77
S
from
p
H 5 to 9. The only conformational change noted was that below
p
H 5 tail plates readily dimerized yielding vis-à-vis dimers with an
S
20,w
of 124
S
. Dissociated plates consisted of three major proteins with molecular weights of 53 K ± 5, 31 K ± 3, and 17 K ± 2 daltons. The amino acid analyses indicated that plates had a composition distinct from fibers and tubes and were relatively rich in tryptophan. Degradation studies with dimethyl sulfoxide (DMSO) indicated that tail plates had a unique biological structure. After treatment with DMSO, and to some extent without DMSO, or from lysates of defective mutants, tetrad structures were observed in the electron microscope. These structures had an amino acid content and relative amounts of types of subunits similar but not identical to intact plates. It was proposed that plates were composed of nine such tetrads giving rise to a structure with six- and threefold symmetry.
Ribonucleoside Triphosphate-Dependent Pyrophosphate Exchange of Reovirus Cores
Authors: Wachsman J. T. , Levin D. H. , Acs G.
Published: January 2020

Reovirus cores catalyze a ribonucleoside triphosphate (rNTP)-dependent pyrophosphate exchange reaction in the presence of all four rNTP species. When rNTP species are tested individually, only guanosine-5′-triphosphate supports pyrophosphate exchange.
Greater Vulnerability of the Infecting Viral Strand of Replicative-Form Deoxyribonucleic Acid of Bacteriophage φX174
Authors: Datta B. , Poddar R. K.
Published: January 2020

Four types of φX-infected cells of
Escherichia coli
CR, a thymine-requiring strain of
E. coli
C, were prepared in which the parental replicative-form deoxyribonucleic acid (RF DNA) was labeled with same specific amounts of bromouracil in (i) both strands, (ii) only the infecting viral strand, (iii) only the complementary strand, and (iv) neither strand. The sensitivity of each type of infected cell toward irradiation by ultraviolet light, visible light, and X rays was measured. The results indicate that a certain amount of radiation damage in the infecting viral strand of the parental RF was more inhibitory to the production of progeny phage than when the damage was in the complementary strand. Similar conclusions were also drawn from “suicide” experiments of the phage-infected complexes containing
32
P of the same specific activity on either strand of the parental RF DNA. The results suggest that the beta decay occurring in the infecting viral strand was more effective in inactivating the plaque-forming ability of the complex.
Superinfection of Simian Virus 40-Transformed Permissive Cells with Simian Virus 40
Authors: Barbanti-Brodano Giuseppe , Swetly Peter , Koprowski Hilary
Published: January 2020

Evidence that the resistance of simian virus (SV40)-transformed permissive cells to superinfection with SV40 is due to lack of virus uptake is presented. When virus uptake is enhanced, the events of infection proceed as in normal permissive cells, resulting in production of infectious virus.
Proteins of Avian Tumor Viruses with Different Coat Antigens
Authors: Robinson William S. , Hung Paul , Robinson Harriet L. , Ralph David D.
Published: January 2020

Isoelectric focusing of avian tumor viruses with distinct type-specific envelope antigens demonstrated no differences in isoelectric points. Viruses with different type-specific antigens were found to contain different glycoprotein components when virion proteins were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis.
Bacteriophage Tail Components
Authors: Kozloff L. M. , Lute M. , Crosby L. K.
Published: January 2020

The assembly of T4D tail plates occurring during in vitro complementation reactions was found to be stimulated by pteroyl hexaglutamate. Neither the pteroyl pentaglutamate nor the pteroyl heptaglutamate substituted for the hexaglutamate. A small stimulation of the rate and amount of T4D tail plate assembly was observed in untreated extracts. A greater stimulation occurred when activated charcoal-treated bacterial extracts were used. Charcoal treatment inhibited complementation only when no preformed tail plates were present in the extracts, and the inhibition was reversed by the addition of 9 × 10
−6
m
chemically synthesized pteroyl hexaglutamate. The stimulation is apparently due to a requirement for the pteroyl hexaglutamate for tail plate assembly.
Isolation and Characterization of a Double-Stranded Ribonucleic Acid from
Penicillium chrysogenum
Authors: Lemke Paul A. , Ness Terence M.
Published: January 2020

Double-stranded ribonucleic acid has been obtained from cells of the fungus
Penicillium chrysogenum.
This ribonucleic acid appears to be associated with mycophage and is an efficient inducer of interferon Its. extraction and partial purification are discussed, and evidence for its double-stranded and ribosidal nature is reviewed. The implications of viral nucleic acid in the life processes of fungi are considered.
Complementary Strands of Bacteriophage φ29 Deoxyribonucleic Acid: Preparative Separation and Transcription Studies
Authors: Mosharrafa E. T. , Schachtele C. F. , Reilly B. E. , Anderson D. L.
Published: January 2020

Bacillus subtilis
phage φ29 has a nonpermuted, duplex deoxyribonucleic acid (DNA) with cohesive ends and a molecular weight of 11 × 10
6
. Denaturation of this DNA yielded two intact polynucleotide chains. Preferential binding of the polyribonucleotide polyuridylic-guanylic acid (poly UG) to the complementary strands of denatured φ29 DNA permitted separation of the strands in neutral CsCl gradients. In analytical CsCl density gradient centrifugation, the separated strands with poly UG appeared as two symmetrical bands, both heavier than the normal denatured DNA band. The strands differed in density by 11 mg/cc. Preparative separation of the φ29 DNA strands resulted in two fractions, heavy (H) and light (L). The H fraction was essentially free from L contamination, whereas L contained up to 25% of H, as determined both by rebanding the separated fractions in CsCl and by electron microscopic examination of self- and mixed-annealed fractions. Pulse-labeled ribonucleic acid (RNA) prepared at intervals after infection was hybridized with the self-annealed DNA strands. Preliminary experiments indicated that both strands of φ29 DNA are transcribed during the development of the virus. Early transcribed φ29-specific RNA hybridizes only with the L strand; at later times, transcription occurs from both the L and H strands.
Organization of the thymidylate synthase gene of herpesvirus saimiri
Authors: Bodemer W , Niller H H , Nitsche N , Scholz B , Fleckenstein B
Published: January 2020

Herpesvirus saimiri codes, unlike most other herpesviruses, for a thymidylate synthase (TS). The TS gene of herpesvirus saimiri is unusual in structure and regulation of expression. It is transcribed into a nonspliced mRNA of 2,190 nucleotides. The single open reading frame of the viral TS gene, instructing a polypeptide of 33.5 kilodaltons, has extensive sequence homology with the corresponding TS coding sequences of human cells and of various procaryotes; the putative polypeptide derived from the nucleotide sequence of the herpesvirus saimiri TS gene is 70% identical with the human enzyme. The untranslated regions of the herpesvirus saimiri TS gene do not share homology with the other characterized eucaryotic or bacterial TS genes. The 5' untranslated sequence has 22 ATG triplets shortly followed by stop codons. The herpesvirus saimiri TS gene, which may be weakly transcribed during immediate early and early times of virus replication, is maximally expressed at the late phase. Various parameters suggest that the TS gene has been acquired in virus evolution by an ancestral herpesvirus from the cellular genome.
Replication of human cytomegalovirus in human peripheral blood T cells
Authors: Braun R W , Reiser H C
Published: January 2020

The replication of human cytomegalovirus (HCMV) strain AD169 was studied in human peripheral blood granulocytes, monocytes-macrophages, B lymphocytes, and T lymphocytes. Progeny virus was produced in some T-cell cultures stimulated in the allogeneic mixed lymphocyte reaction and was regularly obtained when stimulated T cells were grown in the presence of interleukin 2. Replication of HCMV in these cultures was documented by increases in titer, expression of early and late antigen as assessed by indirect immunofluorescence and Western blot, and viral DNA synthesis as determined by dot-blot assays. Approximately 0.05% of cells in virus-producing cultures formed infectious centers, indicating that only a subset of cells takes part in active virus replication. In double-immunofluorescence experiments this subset was found to consist primarily of the T3+ and T8+ phenotype. By infection of preparatively separated T4+ and T8+ T lymphocytes, however, it could be shown that both T-cell subsets were susceptible to HCMV infection as indicated by increases in titer and by DNA kinetics. We conclude from these data that the T lymphocyte might be a target for HCMV in vitro, which is in accordance with in vivo findings in HCMV-infected patients.
Coxsackievirus B3 infection alters plasma membrane of neonatal skin fibroblasts
Authors: Lutton C W , Gauntt C J
Published: January 2020

Replication of coxsackievirus B3 occurred for days in cultures of murine neonatal skin fibroblasts in the absence of cytopathology and resulted in alteration of the plasma membrane. Dual immunofluorescence studies showed that the lectin Ulex europaeus agglutinin I bound only to cells producing viral capsid antigens. Cultures of coxsackievirus B3-inoculated murine neonatal skin fibroblasts showed maximum binding of this lectin at 72 h postinoculation. These data show that in a nonlytic infection a picornavirus can alter the surface of an infected cell.
Modulation of humoral response to a 12-amino-acid site on the poliovirus virion
Authors: Icenogle J P , Minor P D , Ferguson M , Hogle J M
Published: January 2020

Most monoclonal antibodies to poliovirus 3 but not poliovirus 1 require a single 12-amino-acid sequence in virion protein VP1 for neutralization (site 1). None of the available monoclonal antibodies requiring this site bound virions after tryptic cleavage of site 1. This result allowed the amount of site 1-specific antibodies to be determined in an antiserum by comparing its reactivity with virus and trypsin-cleaved virus. Antisera to poliovirus 3 Sabin strain (PS3) but not poliovirus 1 Sabin showed site 1 immunodominance, consistent with the frequency of isolation of site 1-specific monoclonal antibodies to these viruses. Cleavage of site 1 prior to immunization dramatically reduced the immunogenicity of this site in PS3. However, the antiserum against trypsin-cleaved PS3 still had a high neutralization titer, demonstrating that sites other than site 1 can elicit a neutralizing response to PS3. Other antisera to PS3 showed significant variability in the response to site 1, indicating that other factors, such as the genetic background of inbred mouse strains, the species immunized, and the immunization protocol, also affect immunodominance. In particular, a serum from a human infant recently immunized with oral trivalent vaccine had little response to site 1.
Map location of the gene for a 130,000-dalton glycoprotein of bovine herpesvirus 1
Authors: Lawrence W C , D'urso R C , Kundel C A , Whitbeck J C , Bello L J
Published: January 2020

A bovine herpesvirus 1 variant (mar6) containing a mutation in a viral glycoprotein with a molecular weight of 130,000 (g130) was isolated by selecting for resistance to a neutralizing monoclonal antibody (130-6) directed against g130. Mar6 was completely resistant to neutralization by monoclonal antibody 130-6 in the presence and absence of complement, but was neutralized by polyvalent immune sera. The mar6 mutant synthesized and processed g130, but produced plaques which failed to react with monoclonal antibody 130-6 in an in situ immunoassay (black plaque). However, monoclonal antibody 130-6 was capable of binding and immunoprecipitating g130 from infected-cell extracts produced by lysis of mar6-infected cells with nonionic detergents. The mutation in mar6 was mapped by marker rescue with cloned bovine herpesvirus 1 restriction enzyme fragments to a 3.8-kilobase fragment at approximate map units 0.405 to 0.432. In addition, it was found that a DNA probe containing the glycoprotein B gene of herpes simplex type 1 hybridized uniquely to the same 3.8-kilobase fragment which was shown by marker rescue to contain the mutation site in the gene for bovine herpesvirus 1 g130.