Properties of a D-quinovosamine-producing Achromobacter

1968 ◽  
Vol 14 (2) ◽  
pp. 165-171 ◽  
Author(s):  
R. R. Colwell ◽  
E. J. Smith ◽  
G. B. Chapman

The bacterial mucopolysaccharide of a Gram-negative bacterium, Georgetown strain COC-21, includes a hexosamine component, D-quinovosamine. The bacterium has been identified and classified as Achromobacter georgiopolitanum n. sp. and a description of the organism is given. The overall deoxyribonucleic acid base composition, determined by buoyant density measurements in cesium chloride, is 41 moles %. Electron micrographs of ultrathin sections reveal a double-layered cell wall structure typical of the Gram-negative bacteria.

1966 ◽  
Vol 12 (6) ◽  
pp. 1099-1103 ◽  
Author(s):  
R. R. Colwell ◽  
R. V. Citarella ◽  
P. K. Chen

A marine bacterium, NCMB 397, host strain for bacteriophages NCMB 384 and 385, has been subjected to taxonoinic analysis. Overall base composition of the highly purified deoxyribonucleic acid was determined and found to be 37 moles % guanine + cytosine. The phenetic and nucleic acid data suggest significant relationship of this strain and members of the genus Cytophaga. A description of Cytophaga marinoflava n. sp. is presented.


1973 ◽  
Vol 19 (6) ◽  
pp. 753-756
Author(s):  
Terrence M. Hammill ◽  
Geno J. Germano

Glutaraldehyde-fixed, platinum-carbon-shadowed whole mounts, and ultrathin sections of glutaraldehyde-OsO4-fixed cells of Desulfovibrio desulfuricans were observed by electron microscopy. The preparations demonstrated a typical Vibrio form with a single polar flagellum. The cell envelope and the formation of external blebs were shown to be similar to other gram-negative bacteria. The protoplast, apparently devoid of mesosomes or other membranous structures, was densely packed with ribosomes and contained a fibrous nucleoid. A specialized region near the flagellar end of the cell was commonly observed and termed the basal apparatus. Cell division appeared to be by constriction.


2009 ◽  
Vol 55 (5) ◽  
pp. 627-632 ◽  
Author(s):  
Thomas Candela ◽  
Marie Moya ◽  
Michel Haustant ◽  
Agnès Fouet

Poly-γ-glutamate has been described in many Gram-positive organisms. When anchored to the surface, it is a capsule and as such a virulence factor. Based on sequence similarities, few Gram-negative organisms have been suggested to synthesize poly-γ-glutamate. For the first time, a Gram-negative bacterium, Fusobacterium nucleatum , is shown to produce and secrete poly-γ-glutamate. Putative poly-γ-glutamate-synthesizing genes from Gram-negative organisms have been compared with their Gram-positive homologs by in silico analysis, i.e., gene sequence and phylogenetic analysis. Clusters of three instead of four genes were highlighted by our screen. The products of the first two genes display similarity with their Gram-positive equivalents, yet the sequences from the Gram-negative organisms can be distinguished from those of the Gram-positives. Interestingly, the sequence of the predicted product of the third gene is conserved among Gram-negative bacteria but displays no similarity to that of either the third or fourth gene of the Gram-positive operons. It is suggested that, like for Gram-positive bacteria, poly-γ-glutamate has a role in virulence for pathogens and one in survival for other Gram-negative bacteria.


1969 ◽  
Vol 15 (9) ◽  
pp. 1067-1076 ◽  
Author(s):  
A. H. Amin ◽  
T. V. Subbaiah ◽  
K. M. Abbasi

Berberine sulfate was shown to possess antimicrobial activity against a wide variety of microorganisms including Gram-positive and Gram-negative bacteria, fungi, and protozoa. The antibacterial activity against Vibrio cholerae and Staphylococcus aureus was dependent on the inoculum size of the test organism and pH of the medium. A method of microbiological assay sensitive to 5–10 μg/ml of the drug was developed. The drug was shown to exert a more rapid antibacterial activity than chloramphenicol and tetracycline on V. cholerae, the K values being 2.4 ×10−2 sec−1, 7.8 × 10−3 sec−1, and 5.2 × 10−3 sec−1 respectively. Berberine sulfate was shown to be bacteriocidal to V. cholerae and bacteriostatic to S. aureus, at concentrations of 35 and 50 μg/ml. In both these organisms concentrations of 35 and 50 μg/ml of the drug inhibited ribonucleic acid (RNA) and protein synthesis almost immediately after the addition of the drug. There was little effect on deoxyribonucleic acid (DNA) synthesis at these concentrations.


1970 ◽  
Vol 101 (2) ◽  
pp. 333-338 ◽  
Author(s):  
M. Mandel ◽  
Levi Igambi ◽  
Janet Bergendahl ◽  
M. L. Dodson ◽  
E. Scheltgen

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