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Environmental Microbiology Jun 2004'Aegyptianella ranarum' (order Rickettsiales), an ultrastructurally defined small, Gram-negative rod, is known to replicate in the red blood cells of frogs. Heretofore,... (Comparative Study)
Comparative Study
Proposal to transfer 'Aegyptianella ranarum', an intracellular bacterium of frog red blood cells, to the family Flavobacteriaceae as 'Candidatus Hemobacterium ranarum' comb. nov.
'Aegyptianella ranarum' (order Rickettsiales), an ultrastructurally defined small, Gram-negative rod, is known to replicate in the red blood cells of frogs. Heretofore, this bacterium has not been characterized genetically. We cloned and sequenced the 16S rRNA (1310 bp) and gyrB (718 bp) genes of 'A. ranarum' from a Canadian frog blood specimen. In situ hybridization (with an 'A. ranarum' 16S rRNA gene polymerase chain reaction product as probe) and electron microscopy confirmed that 'A. ranarum' forms cytoplasmic inclusions in frog erythrocytes. blast comparisons with GenBank 16S rRNA and gyrB sequences showed that both 'A. ranarum' genes were most similar (91% and 67% identity) to those of Chryseobacterium meningosepticum, a bacterium in the family Flavobacteriaceae. In contrast, 'A. ranarum' 16S rRNA shared only 61% identity with Aegyptianella pullorum. Phylogenetic analyses of these genes using phylip supported 'A. ranarum' as a member of Flavobacteriaceae, but suggested that its cladistic sibling may be Bergeyella zoohelcum or Weeksella virosa, rather than C. meningosepticum. We propose to classify 'Aegyptianella ranarum' as 'Candidatus Hemobacterium ranarum' in the family Flavobacteriaceae. Our results provide a starting point for studies of related intraerythrocytic bacterial infections in frogs.
Topics: Anaplasmataceae; Animals; Anura; Base Sequence; Cluster Analysis; DNA Gyrase; DNA Primers; Erythrocytes; Flavobacteriaceae; In Situ Hybridization; Inclusion Bodies; Microscopy, Electron; Molecular Sequence Data; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Species Specificity
PubMed: 15142244
DOI: 10.1111/j.1462-2920.2004.00559.x -
Journal of Clinical Microbiology May 2003Due to the inadequate automation in the amplification and sequencing procedures, the use of 16S rRNA gene sequence-based methods in clinical microbiology laboratories is...
Usefulness of the MicroSeq 500 16S ribosomal DNA-based bacterial identification system for identification of clinically significant bacterial isolates with ambiguous biochemical profiles.
Due to the inadequate automation in the amplification and sequencing procedures, the use of 16S rRNA gene sequence-based methods in clinical microbiology laboratories is largely limited to identification of strains that are difficult to identify by phenotypic methods. In this study, using conventional full-sequence 16S rRNA gene sequencing as the "gold standard," we evaluated the usefulness of the MicroSeq 500 16S ribosomal DNA (rDNA)-based bacterial identification system, which involves amplification and sequencing of the first 527-bp fragment of the 16S rRNA genes of bacterial strains and analysis of the sequences using the database of the system, for identification of clinically significant bacterial isolates with ambiguous biochemical profiles. Among 37 clinically significant bacterial strains that showed ambiguous biochemical profiles, representing 37 nonduplicating aerobic gram-positive and gram-negative, anaerobic, and Mycobacterium species, the MicroSeq 500 16S rDNA-based bacterial identification system was successful in identifying 30 (81.1%) of them. Five (13.5%) isolates were misidentified at the genus level (Granulicatella adiacens was misidentified as Abiotrophia defectiva, Helcococcus kunzii was misidentified as Clostridium hastiforme, Olsenella uli was misidentified as Atopobium rimae, Leptotrichia buccalis was misidentified as Fusobacterium mortiferum, and Bergeyella zoohelcum was misidentified as Rimerella anatipestifer), and two (5.4%) were misidentified at the species level (Actinomyces odontolyticus was misidentified as Actinomyces meyeri and Arcobacter cryaerophilus was misidentified as Arcobacter butzleri). When the same 527-bp DNA sequences of these seven isolates were compared to the known 16S rRNA gene sequences in the GenBank, five yielded the correct identity, with good discrimination between the best and second best match sequences, meaning that the reason for misidentification in these five isolates was due to a lack of the 16S rRNA gene sequences of these bacteria in the database of the MicroSeq 500 16S rDNA-based bacterial identification system. In conclusion, the MicroSeq 500 16S rDNA-based bacterial identification system is useful for identification of most clinically important bacterial strains with ambiguous biochemical profiles, but the database of the MicroSeq 500 16S rDNA-based bacterial identification system has to be expanded in order to encompass the rarely encountered bacterial species and achieve better accuracy in bacterial identification.
Topics: Bacteria; Bacterial Typing Techniques; Base Sequence; DNA Primers; DNA, Bacterial; DNA, Ribosomal; Humans; Polymerase Chain Reaction; RNA, Bacterial; RNA, Ribosomal, 16S
PubMed: 12734240
DOI: 10.1128/JCM.41.5.1996-2001.2003 -
The Journal of Antimicrobial... Nov 2001We studied the comparative in vitro activity of ertapenem, a new carbapenem, against 240 aerobic and 180 anaerobic recent clinical bite isolates using an agar dilution... (Comparative Study)
Comparative Study
Comparative in vitro activity of ertapenem and 11 other antimicrobial agents against aerobic and anaerobic pathogens isolated from skin and soft tissue animal and human bite wound infections.
We studied the comparative in vitro activity of ertapenem, a new carbapenem, against 240 aerobic and 180 anaerobic recent clinical bite isolates using an agar dilution method and an inoculum of 10(4) cfu/spot for aerobes and 10(5) cfu/spot for anaerobes. Ertapenem inhibited 410/420 (98%) of the isolates tested at < or = 4 mg/L with only 4/5 Campylobacter gracilis and 1/3 Campylobacter rectus strains requiring . or = 16 mg/L for inhibition. Ertapenem was only moderately active (MIC 8 mg/L) against 4/6 Enterococcus faecalis and 1/11 Staphylococcus epidermidis strains. All Pasteurella multocida, Pasteurella septica, Pasteurella canis, Pasteurella dagmatis, Moraxella spp. and EF-4 isolates were inhibited at < or = 0.015 mg/L. MIC(90)s for other aerobic genera and species were as follows: Corynebacterium spp., 4 mg/L; Staphylococcus aureus, 0.25 mg/L; Staphylococcus epidermidis, 4 mg/L; other coagulasenegative staphylococci, 0.25 mg/L; Streptococcus milleri group, 0.5 mg/L; Eikenella corrodens, 0.03 mg/L; and Bergeyella zoohelcum, 0.5 mg/L. For anaerobes the range of MICs and MIC(90)s were: Prevotella ssp., < or = 0.015-0.5, 0.125 mg/L; Porphyromonas spp., < or = 0.015-0.03, 0.015 mg/L; Fusobacterium spp., 0.015-0.125, 0.03 mg/L; Bacteroides tectum, 0.03-0.125, 0.125 mg/L; and Peptostreptococcus spp., 0.01-2, 1 mg/L. Ertapenem showed excellent potency against the full range of animal and human bite wound pathogens.
Topics: Animals; Anti-Bacterial Agents; Bacteria, Aerobic; Bacteria, Anaerobic; Bites, Human; Carbapenems; Humans; Microbial Sensitivity Tests; Skin Diseases, Bacterial; Soft Tissue Infections; Wound Infection
PubMed: 11679553
DOI: 10.1093/jac/48.5.641 -
Antimicrobial Agents and Chemotherapy Sep 2000We studied the comparative in vitro activities of ABT-773, a new ketolide, against 268 aerobic and 148 anaerobic recent isolates from clinical bites using an agar... (Comparative Study)
Comparative Study
We studied the comparative in vitro activities of ABT-773, a new ketolide, against 268 aerobic and 148 anaerobic recent isolates from clinical bites using an agar dilution method and inocula of 10(4) CFU/spot for aerobes and 10(5) CFU for anaerobes. The following are the MIC ranges and MICs at which 90% of isolates are inhibited (MIC(90)s) of ABT-773 for various isolates, respectively: Pasteurella multocida and Pasteurella septica, 0.125 to 2 and 1 microg/ml; other Pasteurella species, 0.125 to 1 and 0.5 microg/ml; Corynebacterium spp., 0.015 to 0.06 and 0.015 microg/ml; Staphylococcus aureus, 0.03 to 0.06 and 0.06 microg/ml; coagulase-negative staphylococci, 0.015 to >32 and 32 microg/ml; streptococci, 0.015 to 0.03 and 0.03 microg/ml; Eikenella corrodens, 0.25 to 1 and 1 microg/ml; and Bergeyella zoohelcum, 0.03 to 0.25 and 0.06 microg/ml. For anaerobes the MIC ranges and MIC(90)s of ABT-773 were as follows, respectively: Prevotella heparinolytica, 0. 06 to 0.125 and 0.125 microg/ml; Prevotella spp., 0.015 to 0.125 and 0.06 microg/ml; Porphyromonas spp., 0.015 to 0.03 and 0.015 microg/ml; Fusobacterium nucleatum, 0.5 to 8 and 8 microg/ml; other Fusobacterium spp., 0.015 to 8 and 0.5 microg/ml; Bacteroides tectum, 0.015 to 0.5 and 0.06 microg/ml; and Peptostreptococcus spp., 0.015 to 0.25 and 0.03 microg/ml. ABT-773 was more active than all macrolides tested against S. aureus, E. corrodens, and anaerobes, but all compounds were poorly active against F. nucleatum. The activity of ABT-773 was within 1 dilution of that of azithromycin against Pasteurella spp., and ABT-773 was four- to eightfold more active than clarithromycin against Pasteurella spp. ABT-773 may offer a therapeutic alternative for bite wound infections.
Topics: Animals; Anti-Bacterial Agents; Bacteria, Aerobic; Bacteria, Anaerobic; Bites and Stings; Erythromycin; Humans; Ketolides; Microbial Sensitivity Tests; Skin Diseases, Bacterial; Soft Tissue Infections
PubMed: 10952607
DOI: 10.1128/AAC.44.9.2525-2529.2000 -
Scientific Reports Feb 2020The white leg Litopenaeus vannamei shrimp is of importance to the eastern Pacific fisheries and aquaculture industry but suffer from diseases such as the recently...
The white leg Litopenaeus vannamei shrimp is of importance to the eastern Pacific fisheries and aquaculture industry but suffer from diseases such as the recently emerged early mortality syndrome. Many bacterial pathogens have been identified but the L. vannamei microbiota is still poorly known. Using a next-generation sequencing (NGS) approach, this work evaluated the impact of the inclusion in the diet of mannan oligosaccharide, (MOS, 0.5% w/w), over the L. vannamei microbiota and production behavior of L. vannamei under intensive cultivation in Ecuador. The MOS supplementation lasted for 60 days, after which the shrimp in the ponds were harvested, and the production data were collected. MOS improved productivity outcomes by increasing shrimp survival by 30%. NGS revealed quantitative differences in the shrimp microbiota between MOS and control conditions. In the treatment with inclusion of dietary MOS, the predominant phylum was Actinobacteria (28%); while the control group was dominated by the phylum Proteobacteria (30%). MOS has also been linked to an increased prevalence of Lactococcus- and Verrucomicrobiaceae-like bacteria. Furthermore, under the treatment of MOS, the prevalence of potential opportunistic pathogens, like Vibrio, Aeromonas, Bergeyella and Shewanella, was negligible. This may be attributable to MOS blocking the adhesion of pathogens to the surfaces of the host tissues. Together, these findings point to the fact that the performance (survival) improvements of the dietary MOS may be linked to the impact on the microbiota, since bacterial lines with pathogenic potential towards shrimps were excluded in the gut.
Topics: Actinobacteria; Aeromonas; Animal Feed; Animals; Aquaculture; Bacterial Adhesion; Ecuador; Flavobacteriaceae; Lactococcus; Longevity; Mannans; Microbiota; Oligosaccharides; Penaeidae; Proteobacteria; Seafood; Shewanella; Verrucomicrobia; Vibrio
PubMed: 32066764
DOI: 10.1038/s41598-020-59587-y -
LakartidningenMicrobiological cultures from 229 patients seeking medical advise in Stockholm after the tsunami catastrophe December 2004 were analysed at the Clinical microbiology... (Comparative Study)
Comparative Study
Microbiological cultures from 229 patients seeking medical advise in Stockholm after the tsunami catastrophe December 2004 were analysed at the Clinical microbiology laboratory, Karolinska University Hospital, Stockholm, Sweden. Gram-negative rods were the most common findings from wound cultures. Common human pathogens as Escherichia coli, Proteus species, Klebsiella spp, and Pseudomonas aeruginosa were isolated. However, more rare species of gram-negative rods were also isolated, e.g. Myroides odoratus, Sphingomonas paucimobilis and Bergeyella zoohelcum. Resistance towards ordinary antibiotics was higher compared to our Swedish reference material for Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis and Acinetobacter spp, but not for Pseudomonas aeruginosa. Possibly, this reflects that the resistant isolates were nosocomially acquired in Asia.
Topics: Bacteriological Techniques; Cross Infection; Disasters; Drug Resistance, Multiple, Bacterial; Gram-Negative Bacteria; Gram-Negative Bacterial Infections; Humans; Sweden; Thailand; Wounds and Injuries
PubMed: 16416946
DOI: No ID Found