bluuebunny/crossref_metadata_2025_split huggingface dataset:
Clinical evaluation of Alfaxan‐CD® as an intravenous anaesthetic in young cats
Authors: Zaki S , Ticehurst KE , Miyaki Y 
Published: February 2009

Objective To describe and evaluate the use of Alfaxan‐CD®as an intravenous anaesthetic in young cats.Design Thirty‐five Domestic Short‐hair cats aged from 3 to 12 months were admitted into the University Veterinary Teaching Hospital‐Sydney for elective surgery. Anaesthesia was induced with Alfaxan‐CD® and maintained with isoflurane: 22 cats received no premedication and 13 cats received acepromazine (0.03 mg/kg) and butorphanol (0.3 mg/kg) subcutaneously 30 min prior to induction.Qualitative and quantitative data for induction and recovery were recorded. Physiological parameters were recorded at 0, 2 and 5 min post induction, and every 5 min thereafter until the end of the procedure.Results Intravenous injection of Alfaxan‐CD® resulted in rapid induction of anaesthesia with a mean time to intubation of 122 s. The mean dose of Alfaxan‐CD® used was 4.2 mg/kg in unpremedicated cats and 2.7 mg/kg in premedicated cats. All cats maintained a heart rate above 95 beats/min. No cat developed hypoxaemia. Hypercapnoea was detected in 4 cats and hypotension was observed in 18 cats. Time to extubation ranged from 1 to 9 min. The mean time to sternal recumbency for premedicated cats was 11 min; 77% of premedicated cats and 23% of unpremedicated cats had a recovery score of 1 or 2.Conclusion Alfaxan‐CD® is an effective anaesthetic agent in young healthy cats, providing a smooth induction and rapid recovery. Cats that were premedicated with acepromazine and butorphanol prior to induction with Alfaxan‐CD® had better recovery scores than those that were not premedicated.
Worm infections in high and low bodyweight Merino ewes during winter and spring
Authors: Larsen JWA , Anderson N 
Published: February 2009

Objective  To compare infections of gastrointestinal nematodes in 2‐year‐old (‘maiden’) spring‐lambing Merino ewes in the upper and lower 25% of body weights (BW) at joining.Design  An observational study over two consecutive years on two farms in western Victoria.Methods  On each farm, ewes were weighed at the end of mating. Ewes within the upper and lower quartile of BW formed two groups that grazed together for the remainder of the year. On each farm, 20 ewes from each group were also treated with controlled release capsules containing ivermectin to minimise the effects of parasitism. Measures of worm infections were worm egg counts, total worm counts and assessment of breech soiling (‘dag score’). Measures of production were BW, numbers of deaths, pregnant ewes and weaned lambs in each group, and response to treatment with a capsule.Results  No consistent difference was found in mean worm egg counts between ewes in the high and low BW groups and total worm counts of ewes before lambing were not significantly different in either year. Breech soiling of low BW ewes was consistently higher on both farms in both years. Those ewes also reared 7% to 14% fewer lambs. The difference in BW between the low and high groups remained highly significant on both farms throughout both years.Conclusion  A strategic approach to worm control is appropriate for ewes in both high and low BW categories. Management options for low BW ewes include culling, supplementary feeding to increase BW before mating, or delaying mating for 12 months.
Dogs Are a Reservoir of Ampicillin-Resistant
Enterococcus faecium
Lineages Associated with Human Infections
Authors: Damborg Peter , Top Janetta , Hendrickx Antoni P. A. , Dawson Susan , Willems Rob J. L. , Guardabassi Luca 
Published: February 2009

ABSTRACT

Ampicillin resistance is a marker for hospital-associated
Enterococcus faecium
. Feces from 208 dogs were selectively screened for the occurrence of ampicillin-resistant
E. faecium
(AREF). AREF was detected in 42 (23%) of 183 dogs screened in a cross-sectional study in the United Kingdom and in 19 (76%) of 25 dogs studied longitudinally in Denmark. AREF carriage was intermittent in all dogs studied longitudinally. Multilocus sequence typing of 63 canine AREF isolates revealed the presence of 13 distinct sequence types. Approximately 76% of the isolates belonged to hospital-adapted clonal complex 17 (CC17), including those of sequence types ST-78 and ST-192, which are widespread in European and Asian hospitals. Longitudinal screening of 18 healthy humans living in contact with 13 of the dogs under study resulted in the identification of a single, intermittent CC17 carrier. This person carried one of the sequence types (ST-78) recovered from his dog. Based on PCR and Southern hybridization analyses, the putative virulence gene cluster from
orf903
to
orf907
was widespread in canine AREF isolates (present in 97%), whereas
orf2351
(present in 26% of isolates) and
orf2430
(present in 31%) were strongly associated with CC17-related sequence types (
P
< 0.05). Surprisingly,
esp
and
hyl
were not detected in any of the isolates. The antimicrobial resistance profiles of canine AREF isolates generally differed from those previously described for clinical human isolates. The results indicate that dogs are frequent carriers of CC17-related lineages and may play a role in the spread of this nosocomial pathogen. The distinctive virulence and antimicrobial resistance profiles observed among canine AREF isolates raise interesting questions about the origin and evolution of the strains causing human infections.
Different Patterns of Regulation for the Copper and Cadmium Metallothioneins of the Ectomycorrhizal Fungus
Hebeloma cylindrosporum
Authors: Ramesh G. , Podila G. K. , Gay G. , Marmeisse R. , Reddy M. S. 
Published: February 2009

ABSTRACT

Metallothioneins (MTs) are small cysteine-rich peptides involved in metal homeostasis and detoxification. We have characterized two MT genes, Hc
MT1
and Hc
MT2
, from the ectomycorrhizal fungus
Hebeloma cylindrosporum
in this study. Expression of Hc
MT1
and Hc
MT2
in
H. cylindrosporum
under metal stress conditions was studied by competitive reverse transcription-PCR analysis. The full-length cDNAs were used to perform functional complementation in mutant strains of
Saccharomyces cerevisiae
. As revealed by heterologous complementation assays in yeast, Hc
MT1
and Hc
MT2
each encode a functional polypeptide capable of conferring increased tolerance against Cd and Cu, respectively. The expression levels of Hc
MT1
were observed to be at their maximum at 24 h, and they increased as a function of Cu concentration. Hc
MT2
was also induced by Cu, but the expression levels were lower than those for Hc
MT1
. The mRNA accumulation of Hc
MT1
was not influenced by Cd, whereas Cd induced the transcription of Hc
MT2
. Zn, Pb, and Ni did not affect the transcription of Hc
MT1
or of Hc
MT2
. Southern blot analysis revealed that both of these genes are present as a single copy in
H. cylindrosporum
. While the promoters of both Hc
MT1
and Hc
MT2
contained the standard stress response elements implicated in the metal response, the numbers and varieties of potential regulatory elements were different in these promoters. These results show that ectomycorrhizal fungi encode different MTs and that each of them has a particular pattern of expression, suggesting that they play critical specific roles in improving the survival and growth of ectomycorrhizal trees in ecosystems contaminated by heavy metals.
Use of Calcofluor White for Detection, Identification, and Quantification of Phytoplanktonic Fungal Parasites
Authors: Rasconi Serena , Jobard Marlène , Jouve Lionel , Sime-Ngando Télesphore 
Published: February 2009

ABSTRACT
We propose a routine protocol based on size fractionation of pelagic samples and the use of the fluorochrome calcofluor white (which binds to β-1,3 and β-1,4 polysaccharides) for diagnosing, identifying, and counting chitinaceous fungal parasites (i.e., the sporangia of chytrids) of phytoplankton. The protocol was applied to freshwater samples collected during different seasons (spring and summer/autumn) in two lakes whose trophic statuses varied. Because few samples were collected (i.e., two dates per site), the findings are considered preliminary and mainly a “proof of concept” rather than a valid comparison of sites versus seasons. The results from the proposed protocol indicate higher diversity of infected host and parasite communities than in previous studies. Chytrid epidemics were omnipresent, infecting diverse phytoplankton host communities, primarily diatoms, chlorophytes, and colonial and filamentous cyanobacteria. The diversity and numerical abundance of sporangia and of hosts, and the prevalence of infection (range, <1 to 24% of total host cells) as well, increased from the oligotrophic Lake Pavin to the eutrophic Lake Aydat, while the temporal changes in parasites were apparently more influenced by the host community composition. We conclude that the proposed protocol offers a valid method for the quantitative ecology of chytrid epidemics in aquatic ecosystems and food web dynamics.
Stimulation of Expression of a Silica-Induced Protein (Sip) in
Thermus thermophilus
by Supersaturated Silicic Acid
Authors: Doi Katsumi , Fujino Yasuhiro , Inagaki Fumio , Kawatsu Ryouichi , Tahara Miki , Ohshima Toshihisa , Okaue Yoshihiro , Yokoyama Takushi , Iwai Satoru , Ogata Seiya 
Published: February 2009

ABSTRACT

The effects of silicic acid on the growth of
Thermus thermophilus
TMY, an extreme thermophile isolated from a siliceous deposit formed from geothermal water at a geothermal power plant in Japan, were examined at 75°C. At concentrations higher than the solubility of amorphous silica (400 to 700 ppm SiO
2
), a silica-induced protein (Sip) was isolated from the cell envelope fraction of log-phase TMY cells grown in the presence of supersaturated silicic acid. Two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed the molecular mass and pI of Sip to be about 35 kDa and 9.5, respectively. Induction of Sip expression occurred within 1 h after the addition of a supersaturating concentration of silicic acid to TM broth. Expression of Sip-like proteins was also observed in other thermophiles, including
T. thermophilus
HB8 and
Thermus aquaticus
YT-1. The amino acid sequence of Sip was similar to that of the predicted solute-binding protein of the Fe
3+
ABC transporter in
T. thermophilus
HB8 (locus tag, TTHA1628; GenBank accession no. NC_006461; GeneID, 3169376). The
sip
gene (987-bp) product showed 87% identity with the TTHA1628 product and the presumed Fe
3+
-binding protein of
T. thermophilus
HB27 (locus tag TTC1264; GenBank accession no. NC_005835; GeneID, 2774619). Within the genome,
sip
is situated as a component of the Fbp-type ABC transporter operon, which contains a palindromic structure immediately downstream of
sip
. This structure is conserved in other
T. thermophilus
genomes and may function as a terminator that causes definitive Sip expression in response to silica stress.
Characterization of a β-Glucoside Operon (bgc) Prevalent in Septicemic and UropathogenicEscherichia coliStrains
Authors: Neelakanta Girish , Sankar T. Sabari , Schnetz Karin 
Published: February 2009

ABSTRACTEscherichia colistrains, in general, do not ferment cellobiose and aryl-β-d-glucosidic sugars, although “cryptic” β-d-glucoside systems have been characterized. Here we describe an additional cryptic operon (bgc) for the utilization of cellobiose and the aryl-β-d-glucosides arbutin and salicin at low temperature. Thebgcoperon was identified by the characterization of β-glucoside-positive mutants of anE. colisepticemia strain (i484) in which the well-studiedbgl(aryl-β-d-glucoside) operon was deleted. Thesebgc* mutants appeared after 5 days of incubation on salicin indicator plates at 28°C. Thebgcoperon codes for proteins homologous to β-glucoside/cellobiose-specific phosphoenolpyruvate-dependent phosphotransfer system permease subunits IIB (BgcE), IIC (BgcF), and IIA (BgcI); a porin (BgcH); and a phospho-β-d-glucosidase (BgcA). Next to thebgcoperon maps the divergentbgcRgene, which encodes a GntR-type transcriptional regulator. Expression of thebgcoperon is dependent on the cyclic-AMP-dependent regulator protein CRP and positively controlled by BgcR. In thebgc* mutants, a single nucleotide exchange enhances the activity of thebgcpromoter, rendering it BgcR independent. Typing of a representative collection ofE. colidemonstrated the prevalence ofbgcin strains of phylogenetic group B2, representing mainly extraintestinal pathogens, while it is rare among commensalE. colistrains. Thebgclocus is also present in the closely related speciesEscherichia albertii. Further, bioinformatic analyses demonstrated that homologs of thebgcgenes exist in the enterobacterialKlebsiella,Enterobacter, andCitrobacterspp. and also in gram-positive bacteria, indicative of horizontal gene transfer events.
Effect of Temperature on the Biotic Potential of Honeybee Microsporidia
Authors: Martín-Hernández Raquel , Meana Aránzazu , García-Palencia Pilar , Marín Pilar , Botías Cristina , Garrido-Bailón Encarna , Barrios Laura , Higes Mariano 
Published: February 2009

ABSTRACT

The biological cycle of
Nosema
spp. in honeybees depends on temperature. When expressed as total spore counts per day after infection, the biotic potentials of
Nosema apis
and
N. ceranae
at 33°C were similar, but a higher proportion of immature stages of
N. ceranae
than of
N. apis
were seen. At 25 and 37°C, the biotic potential of
N. ceranae
was higher than that of
N. apis
. The better adaptation of
N. ceranae
to complete its endogenous cycle at different temperatures clearly supports the observation of the different epidemiological patterns.
Contrasting Roles of Checkpoint Proteins as Recombination Modulators at Fob1-
Ter
Complexes with or without Fork Arrest
Authors: Mohanty Bidyut K. , Bairwa Narendra K. , Bastia Deepak 
Published: February 2009

ABSTRACT

The replication terminator protein Fob1 of
Saccharomyces cerevisiae
specifically interacts with two tandem
Ter
sites (replication fork barriers) located in the nontranscribed spacer of ribosomal DNA (rDNA) to cause polar fork arrest. The Fob1-
Ter
complex is multifunctional and controls other DNA transactions such as recombination by multiple mechanisms. Here, we report on the regulatory roles of the checkpoint proteins in the initiation and progression of recombination at Fob1-
Ter
complexes. The checkpoint adapter proteins Tof1 and Csm3 either positively or negatively controlled recombination depending on whether it was provoked by polar fork arrest or by transcription, respectively. The absolute requirements for these proteins for inducing recombination at an active replication terminus most likely masked their negative modulatory role at a later step of the process. Other checkpoint proteins of the checkpoint adapter/mediator class such as Mrc1 and Rad9, which channel signals from the sensor to the effector kinase, tended to suppress recombination at Fob1-
Ter
complexes regardless of how it was initiated. We have also discovered that the checkpoint sensor kinase Mec1 and the effector Rad53 were positive modulators of recombination initiated by transcription but had little effect on recombination at
Ter
. The work also showed that the two pathways were Rad52 dependent but Rad51 independent. Since
Ter
sites occur in the intergenic spacer of rDNA from yeast to humans, the mechanism is likely to be of widespread occurrence.
LpqM, a Mycobacterial Lipoprotein-Metalloproteinase, Is Required for Conjugal DNA Transfer inMycobacterium smegmatis
Authors: Nguyen Kiet T. , Piastro Kristina , Derbyshire Keith M. 
Published: February 2009

ABSTRACTWe have previously described a novel conjugal DNA transfer process that occurs inMycobacterium smegmatis. To identify donor genes required for transfer, we have performed a transposon mutagenesis screen; we report here that LpqM, a putative lipoprotein-metalloproteinase, is essential for efficient DNA transfer. Bioinformatic analyses predict that LpqM contains a signal peptide necessary for the protein's targeting to the cell envelope and a metal ion binding motif, the likely catalytic site for protease activity. Using targeted mutagenesis, we demonstrate that each of these motifs is necessary for DNA transfer and that LpqM is located in the cell envelope. The requirement for transfer is specific to the donor strain; anlpqMknockout mutant in the recipient is still proficient in transfer assays. The activity of LpqM is conserved among mycobacteria; homologues from bothMycobacterium tuberculosisandMycobacterium aviumcan complementlpqMdonor mutants, suggesting that the homologues recognize and process similar proteins. Lipoproteins constitute a significant proportion of the mycobacterial cell wall, but despite their abundance, very few have been assigned an activity. We discuss the potential role of LpqM in DNA transfer and the implications of the conservation of LpqM activity inM. tuberculosis.
The Tubulin-Like RepX Protein Encoded by the pXO1 Plasmid Forms Polymers In Vivo inBacillus anthracis
Authors: Akhtar Parvez , Anand Syam P. , Watkins Simon C. , Khan Saleem A. 
Published: February 2009

ABSTRACTBacillus anthraciscontains two megaplasmids, pXO1 and pXO2, that are critical for its pathogenesis. Stable inheritance of pXO1 inB. anthracisis dependent upon the tubulin/FtsZ-like RepX protein encoded by this plasmid. Previously, we have shown that RepX undergoes GTP-dependent polymerization in vitro. However, the polymerization properties and localization pattern of RepX in vivo are not known. Here, we utilize a RepX-green fluorescent protein (GFP) fusion to show that RepX forms foci and three distinct forms of polymeric structures inB. anthracisin vivo, namely straight, curved, and helical filaments. Polymerization of RepX-GFP as well as the nature of polymers formed were dependent upon concentration of the protein inside theB. anthraciscells. RepX predominantly localized as polymers that were parallel to the length of the cell. RepX also formed polymers inEscherichia coliin the absence of other pXO1-encoded products, showing that in vivo polymerization is an inherent property of the protein and does not require either the pXO1 plasmid or proteins unique toB. anthracis. Overexpression of RepX did not affect the cell morphology ofB. anthraciscells, whereas it drastically distorted the cell morphology ofE. colihost cells. We discuss the significance of our observations in view of the plasmid-specific functions that have been proposed for RepX and related proteins encoded by several megaplasmids found in members of theBacillus cereusgroup of bacteria.
Divisome under Construction: Distinct Domains of the Small Membrane Protein FtsB Are Necessary for Interaction with Multiple Cell Division Proteins
Authors: Gonzalez Mark D. , Beckwith Jon 
Published: February 2009

ABSTRACTCell division in bacteria requires the coordinated action of a set of proteins, the divisome, for proper constriction of the cell envelope. Multiple protein-protein interactions are required for assembly of a stable divisome. Within theEscherichia colidivisome is a conserved subcomplex of inner membrane proteins, the FtsB/FtsL/FtsQ complex, which is necessary for linking the upstream division proteins, which are predominantly cytoplasmic, with the downstream division proteins, which are predominantly periplasmic. FtsB and FtsL are small bitopic membrane proteins with predicted coiled-coil motifs, which themselves form a stable subcomplex that can recruit downstream division proteins independently of FtsQ; however, the details of how FtsB and FtsL interact together and with other proteins remain to be characterized. Despite the small size of FtsB, we identified separate interaction domains of FtsB that are required for interaction with FtsL and FtsQ. The N-terminal half of FtsB is necessary for interaction with FtsL and sufficient, when in complex with FtsL, for recruitment of downstream division proteins, while a portion of the FtsB C terminus is necessary for interaction with FtsQ. These properties of FtsB support the proposal that its main function is as part of a molecular scaffold to allow for proper formation of the divisome.
Novel
trans
-Acting
Bacillus subtilis glnA
Mutations That Derepress
glnRA
Expression
Authors: Fisher Susan H. , Wray Lewis V. 
Published: February 2009

ABSTRACT

Bacillus subtilis
contains two nitrogen transcription factors, GlnR and TnrA. The activities of GlnR and TnrA are regulated by direct protein-protein interactions with the feedback-inhibited form of glutamine synthetase (GS). To look for other factors involved in regulating GlnR activity, we isolated mutants with constitutive
glnRA
expression (Gln
C
). The twenty-seven Gln
C
mutants isolated in this mutant screen all contained mutations tightly linked to the
glnRA
operon which encodes GlnR (
glnR
) and GS (
glnA
). Four Gln
C
mutants contained mutations in the
glnR
gene that most likely impair the ability of GlnR to bind DNA. Three other Gln
C
mutants contained novel
glnA
mutations (S55F, V173I, and L174F). GlnR regulation was completely relieved in the three
glnA
mutants, while only modest defects in TnrA regulation were observed. In vitro enzymatic assays showed that the purified S55F mutant enzyme was catalytically defective while the V173I and L174F enzymes were highly resistant to feedback inhibition. The V173I and L174F GS proteins were found to require higher glutamine concentrations than the wild-type GS to regulate the DNA-binding activities of GlnR and TnrA in vitro. These results are consistent with a model where feedback-inhibited GS is the only cellular factor involved in regulating the activity of GlnR in
B. subtilis
.
Modulation of Deoxysugar Transfer by the Elloramycin Glycosyltransferase ElmGT through Site-Directed Mutagenesis
Authors: Ramos Angelina , Olano Carlos , Braña Alfredo F. , Méndez Carmen , Salas José A. 
Published: February 2009

ABSTRACT

The glycosyltransferase ElmGT from
Streptomyces olivaceus
is involved in the biosynthesis of the antitumor drug elloramycin, and it has been shown to possess a broad deoxysugar recognition pattern, being able to transfer different
l
- and
d
-deoxysugars to 8-demethyl-tetracenomycin C, the elloramycin aglycone. Site-directed mutagenesis in residues L309 and N312, located in the α/β/α motif within the nucleoside diphosphate-sugar binding region, can be used to modulate the substrate flexibility of ElmGT, making it more precise for transfer of specific deoxysugars.
Formation and Metabolism of Methylmalonyl Coenzyme A in
Corynebacterium glutamicum
Authors: Botella Laure , Lindley Nic D. , Eggeling Lothar 
Published: February 2009

ABSTRACT

Genome sequence information suggests that B
12
-dependent mutases are present in a number of bacteria, including members of the suborder
Corynebacterineae
like
Mycobacterium tuberculosis
and
Corynebacterium glutamicum
. We here functionally identify a methylmalonyl coenzyme A (CoA) mutase in
C. glutamicum
that is retained in all of the members of the suborder
Corynebacterineae
and is encoded by NCgl1471, NCgl1472, and NCgl1470. In addition, we observe the presence of methylmalonate in
C. glutamicum
, reaching concentrations of up to 757 nmol g (dry weight)
−1
in propionate-grown cells, whereas in
Escherichia coli
no methylmalonate was detectable. As demonstrated with a mutase deletion mutant, the presence of methylmalonate in
C. glutamicum
is independent of mutase activity but possibly due to propionyl-CoA carboxylase activity. During growth on propionate, increased mutase activity has severe cellular consequences, resulting in growth arrest and excretion of succinate. The physiological context of the mutase present in members of the suborder
Corynebacterineae
is discussed.