Genotypic and Phenotypic Characterization of Treponema phagedenis from Bovine Digital Dermatitis

This study aimed to isolate and characterize Treponema spp. from bovine digital dermatitis (BDD)-infected dairy cattle. Seven isolates were characterized in this study. Isolates exhibited slow growth, and colonies penetrated the agar and exhibited weak β-hemolysis. Round bodies were observed in old and antibiotic-treated cultures. Cells ranged from 9–12 µm in length, 0.2–2.5 µm in width, and were moderately spiraled. The 16S rRNA analysis revealed the isolates as Treponema phagedenis with >99% sequence homology. Isolates had alkaline phosphatase, acid phosphatase, β-galactosidase, N-acetyl-β-glucosaminidase, esterase (C4), esterase lipase (C8), naphthol-AS-BI-phosphohydrolase, and β-glucuronidase activities. Low concentrations of ampicillin, erythromycin, and tetracycline were required to inhibit the growth of isolates. Formic, acetic, and butyric acids were produced, while propionic acid was significantly utilized, indicating its essentiality for treponemal growth. The isolates shared the same characteristics and, therefore, were considered as a single strain. Isolate HNL4 was deposited as a representative isolate (Treponema phagedenis KS1). The average nucleotide identity of strain KS1 showed a small difference with the human strain (99.14%) compared with bovine strain (99.72%). This study was the first to isolate and characterize Treponema phagedenis from BDD in Korea and, hence, it delivered pathogenicity-related insights and provided valuable information that can be used for the management of BDD.

Download Full-text

Identification of CtpL as a Chromosomally Encoded Chemoreceptor for 4-Chloroaniline and Catechol in Pseudomonas aeruginosa PAO1

Applied and Environmental Microbiology ◽

10.1128/aem.02428-13 ◽

2013 ◽

Vol 79 (23) ◽

pp. 7241-7248 ◽

Cited By ~ 16

Author(s):

Alisa S. Vangnai ◽

Kazuki Takeuchi ◽

Shota Oku ◽

Naoya Kataoka ◽

Tisana Nitisakulkan ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Bacterial Chemotaxis ◽

Transformation Product ◽

Phenotypic Characterization ◽

Aromatic Pollutants ◽

Content Type ◽

Environmental Bacterium ◽

Dead End ◽

Low Concentrations

ABSTRACTBacterial chemotaxis influences the ability of bacteria to survive and thrive in most environments, including polluted ones. Despite numerous reports of the phenotypic characterization of chemotactic bacteria, only a few molecular details of chemoreceptors for aromatic pollutants have been described. In this study, the molecular basis of chemotaxis toward an environmentally toxic chlorinated aromatic pollutant, 4-chloroaniline (4CA), was evaluated. Among the threePseudomonasspp. tested,Pseudomonas aeruginosaPAO1 exhibited positive chemotaxis both to the nonmetabolizable 4CA, where 4-chloroacetanilide was formed as a dead-end transformation product, and to the metabolizable catechol. Molecular analysis of all 26 mutants with a disrupted methyl-accepting chemotaxis gene revealed that CtpL, a chromosomally encoded chemoreceptor, was responsible for the positive chemotactic response toward 4CA. Since CtpL has previously been described to be a major chemoreceptor for inorganic phosphate at low concentrations in PAO1, this report describes a fortuitous ability of CtpL to function toward aromatic pollutants. In addition, its regulation not only was dependent on the presence of the chemoattractant inducer but also was regulated by conditions of phosphate starvation. These results expand the range of known chemotactic transducers and their function in the environmental bacterium PAO1.

Download Full-text

Phenotypic characterization of the Xenorhabdus bacterial symbiont of a Texas strain of the entomopathogenic nematode Steinernema riobrave, and characterization of the Xenorhabdus bovienii bacterial symbiont of a Newfoundland strain of Steinernema feltiae

Canadian Journal of Microbiology ◽

10.1139/w00-036 ◽

2000 ◽

Vol 46 (7) ◽

pp. 618-622 ◽

Cited By ~ 2

Author(s):

Hongjun He ◽

Roger Gordon ◽

John A Gow

Keyword(s):

Entomopathogenic Nematodes ◽

Entomopathogenic Nematode ◽

Bacterial Symbiont ◽

The Other ◽

Steinernema Feltiae ◽

Phenotypic Characterization ◽

Bacterial Symbionts ◽

European Origin ◽

Low Concentrations

Two bacterial symbionts of entomopathogenic nematodes, one of which originated from Texas, U.S.A., and the other from Newfoundland, Canada, were characterized phenotypically. These strains belonged to the genus Xenorhabdus. The Newfoundland (NF) strain was shown to be X. bovienii but the Texas (TX) strain was not identified at the species level. Four additional cultures of Xenorhabdus were included in the study. These were a strain of X. bovienii (Umeå), which was from a nematode of European origin, and strains of X. nematophilus, X.beddingii, and X.poinarii. The tests used in this study indicated identical properties for the NF (North American) and Umeå (European) strains of X. bovienii. These could be differentiated from the other strains studied by their failure to grow at 34°C and resistance to low concentrations of a mixture of amoxilline and clavulanic acid. The Xenorhabdus TX strain could be differentiated from the other strains studied by its failure to grow at 10°C. Of the tests done, approximately 30 were useful in distinguishing between the strains and species studied.Key words: symbionts, nematode, Steinernema, Xenorhabdus, Xenorhabdus bovienii.

Download Full-text

TheAspergillus nidulans musNGene Encodes a RecQ Helicase That Interacts With the PI-3K-Related Kinase UVSB

Genetics ◽

10.1093/genetics/159.4.1595 ◽

2001 ◽

Vol 159 (4) ◽

pp. 1595-1604 ◽

Cited By ~ 3

Author(s):

Amy F Hofmann ◽

Steven D Harris

Keyword(s):

Dna Damage ◽

Homologous Recombination ◽

Dna Damage Response ◽

Slow Growth ◽

Phenotypic Characterization ◽

Null Mutant ◽

Recq Helicase ◽

Present Evidence ◽

Damage Response

AbstractIn Aspergillus nidulans, the uvsB gene encodes a member of the PI-3K-related kinase family of proteins. We have recently shown that UVSB is required for multiple aspects of the DNA damage response. Since the musN227 mutation is capable of partially suppressing defects caused by uvsB mutations, we sought to understand the mechanism underlying the suppression by cloning the musN gene. Here, we report that musN encodes a RecQ helicase with homology to S. pombe rqh1, S. cerevisiae sgs1, and human BLM and WRN. Phenotypic characterization of musN mutant alleles reveals that MUSN participates in the response to a variety of genotoxic agents. The slow growth and genotoxin sensitivity of a musN null mutant can be partially suppressed by a defect in homologous recombination caused by the uvsC114 mutation. In addition, we present evidence suggesting that MUSN may promote recovery from the DNA damage response. We suggest that a block to recovery caused by the musN227 mutation, coupled with the modest accumulation of recombination intermediates, can suppress defects caused by uvsB mutations. Finally, we report that another RecQ helicase, ORQA, performs a function that partially overlaps that of MUSN.

Download Full-text

Map positions of third chromosomal female sterile and lethal mutations of Drosophila melanogaster

Genome ◽

10.1139/g04-052 ◽

2004 ◽

Vol 47 (5) ◽

pp. 832-838 ◽

Cited By ~ 2

Author(s):

Christopher Schuetze ◽

Michelle Peters ◽

Jia-Jen Duong ◽

Matthieu Cavey ◽

Ruth Dörig ◽

...

Keyword(s):

Drosophila Melanogaster ◽

Maternal Effect ◽

Slow Growth ◽

Phenotypic Characterization ◽

Female Sterility ◽

Induced Mutations ◽

Position Effects ◽

Chromosomal Site ◽

Chromosomal Mutations

Chromosomal mutations induced by ethyl methanesulfonate (EMS) treatment can cause female sterility or maternal-effect lethality in Drosophila. EMS is particularly useful to researchers because it creates mutations independent of position effects. However, because researchers have little control over the chromosomal site of mutation, post-mutagenic genetic mapping is required to determine the cytological location of the mutation. To make a valuable set of mutants more useful to the research community, we have mapped the uncharacterized part of the female-sterile – maternal-effect lethal Tübingen collection. We mapped 49 female-sterile – maternal-effect lethal alleles and 72 lethal alleles to individual deficiency intervals on the third chromosome. In addition, we analyzed the phenotype of ovaries resulting from female sterile mutations. The observed phenotypes range from tumorous ovaries and early blocks in oogenesis, to later blocks, slow growth, blocks in stage 10, to apparently full development of the ovary. The mapping and phenotypic characterization of these 121 mutations provide the necessary information for the researcher to consider a specific mutant as a candidate for their gene of interest.Key words: Drosophila melanogaster, oogenesis, female sterile, maternal-effect lethal, EMS-induced mutations.

Download Full-text