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C Ash

Publications and source records attributed to C Ash.

36 records · Page 2Linked to original sources

Vector competence.

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Journal Article↗

Limited tolerance.

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Journal Article↗

Iron in the cell.

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Journal Article↗

Self-control.

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Journal Article↗

Comparative analysis of Bacillus anthracis, Bacillus cereus, and related species on the basis of reverse transcriptase sequencing of 16S rRNA.

The primary structures of the 16S rRNAs of Bacillus anthracis, Bacillus cereus, Bacillus mycoides, and Bacillus thuringiensis were determined by using the reverse transcription-dideoxy sequencing method. All of the strains exhibited very high levels of sequence similarity (greater than 99%) that were consistent with the close relationships shown by previous DNA hybridization studies. The sequences of B. anthracis Sterne and B. cereus emetic strain NCTC 11143 were found to be identical for a continuous stretch of 1,446 bases and differed from the sequence of B. cereus NCDO 1771T (T = type strain) by only a single nucleotide. The 16S rRNA sequences of B. mycoides and B. thuringiensis differed from each other and from the sequences of B. anthracis and B. cereus by four to nine nucleotides.

Bacillus anthracis↗

16S ribosomal ribonucleic acid sequence analyses of lactococci and related taxa. Description of Vagococcus fluvialis gen. nov., sp. nov.

The phylogenetic status of members of the genus Lactococcus and some motile strains which react with Lancefield group N antiserum was examined by reverse transcriptase sequencing of 16S ribosomal ribonucleic acid. In agreement with earlier nucleic acid hybridization and immunological studies of superoxide dismutase the 16S sequence data clearly demonstrate that the lactococci represent a distinct phylogenetic group equivalent in rank to the genera Enterococcus and Streptococcus. The motile group N strains from chicken faeces and river water, however, were found to be phylogenetically unrelated to lactococci but displayed a closer, albeit loose, association with members of the genus Enterococcus. On the basis of the present sequence data and earlier chemotaxonomic studies it is proposed that the motile group N strains be classified in a new genus Vagococcus, as Vagococcus fluvialis sp. nov. The type strain of V. fluvialis is NCDO 2497.

Animals↗

Nematodirus battus: development of cold hardiness in dormant eggs.

Thermistors and an amplified bridge were used to detect supercooling points of Nematodirus battus eggs weighing ca. 1 microgram wet weight. A cooling rate of about 1 C min-1 was achieved with a manually controlled cold stage using the Peltier effect. The supercooling point of eggs fell during chilling at 5 +/- 1 C for up to 8 weeks from -34.48 +/- 0.49 C to -37.17 +/- 0.76 C. Juveniles freed from these eggs were less cold hardy than intact eggs but chilling improved their supercooling to a greater extent from -19.33 +/- 1.38 C to -32.10 +/- 0.68 C. These results were obtained with eggs showing the characteristic hatching response for this species after transfer from chilling at 5 C to higher temperatures (5-37 +/- 1 C). The results indicate eggs of N. battus acclimate to chilling at a time when previous work had established an increase in their trehalose content.

Animals↗

Impact of Nippostrongylus brasiliensis (Nematoda) on the serum albumin and amino acid concentrations of rats fed adequate or protein-deficient diets.

Food intake, body weight changes, serum protein and amino acid concentrations were measured during the course of primary infections of Nippostrongylus brasiliensis in rats fed on either a 2% protein (casein) diet or a 16% protein diet (Oxoid 41 B). Total serum protein concentration declined from 77.84 +/- 5.35 mg/ml in uninfected well-nourished rats to 54 +/- 3.29 mg/ml in rats at 9 days post-infection (p.i.). A reduction from 47.80 +/- 2.78 to 40.38 +/- 5.62 mg/ml had occurred in protein-malnourished rats by day 6 p.i. The hypoproteinaemia was accompanied by significant hypoalbuminaemia in the protein-malnourished rats and concentrations fell from approximately 33 to 19 mg/ml at the time of peak infection. Six days after inoculation, a significant increase was detected in the concentration of serum amino acids in both well-nourished and protein-malnourished rats; the effect was more prolonged for non-essential than for essential amino acids. The results are discussed briefly in relation to recent work on the control of protein metabolism during malnutrition.

Amino Acids↗

Nematodirus battus: permeability changes, calcium binding, and phosphorylation of the eggshell during hatching.

Eggshells of Nematodirus battus leaked trehalose 4 hr after being stimulated to hatch, and became permeable to trypan blue at their poles; 80% of eggs were stained blue 24 hr later. Exogenous application of ruthenium red significantly inhibited chill- and sodium fluoride-stimulated hatching, 50% hatch inhibition occurring in 44.67 +/- 2.2 and 8.5 +/- 1.5 microM, respectively. Lanthanum chloride, however, was not as inhibitory as ruthenium red on fluoride-stimulated hatching, 50% occurring at 31.60 +/- 1.25 microM. A Scatchard plot of the competitive binding of ruthenium red to eggshells demonstrated a high-affinity binding site for calcium, KCa' = 1.92 microM and a second, low-affinity site, KCa" = 1169.60 microM. Ruthenium red binding was significantly reduced by several enzymes, e.g., EGTA-buffered trypsin reduced binding by 73%. Radioiodinated concanavalin A also bound competitively to the eggshells in the presence of alpha-D-glucosyl-alpha-D-glucopyranoside and alpha-methyl-D-mannopyranoside. Eggshells incorporated phosphorus-32 from ATP after chilling or on exposure to sodium fluoride; gel filtration of solubilized homogenates of these samples showed that two proteins were radiolabelled with molecular weights of 38 X 10(3) and 8 X 10(3) Da, respectively. This phosphorylation was inhibited by N-ethylmaleimide, which also prevented hatching.

Adenosine Triphosphate↗

Molecular identification of rRNA group 3 bacilli (Ash, Farrow, Wallbanks and Collins) using a PCR probe test. Proposal for the creation of a new genus Paenibacillus.

Comparative 16S rRNA sequence analysis has demonstrated that the genus Bacillus consists of at least five phyletic lines. rRNA group 3 bacilli of Ash, Farrow, Wallbanks and Collins (1991) comprising Bacillus polymyxa and close relatives is phylogenetically so removed from Bacillus subtilis, the type species of the genus and other aerobic, endospore-forming bacilli that they warrant reclassification in a new genus Paenibacillus. The genus Paenibacillus can be readily distinguished from other Bacillus groups using a battery of phenotypic characters and a highly specific gene probe based on 16S rRNA.

Bacillus↗