Effect of Novobiocin on Fowl Cholera in Turkeys

Hamdy, A. H.; Blanchard, C. J.

doi:10.2307/1588648

Cited by 5 publications

(2 citation statements)

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“…These results are consistent with previous studies that have established the in vitro and in vivo susceptibility of P. multocida to these compounds (1,8,9,12,36). P. aeruginosa was included for reference purposes and was found to be susceptible to oxytetracycline (12.80 ,ug/ml) and polymyxin B (1.95 ,ug/ml) but resistant to novobiocin (>102.4 ,ug/ml).…”

Section: Resultssupporting

confidence: 91%

Variability of cell surface hydrophobicity among Pasteurella multocida somatic serotype and Actinobacillus lignieresii strains

Darnell¹,

Hart²,

Champlin³

1987

J Clin Microbiol

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Pasteurella multocida possesses a characteristically gram-negative ultrastructure, yet its inability to grow in the presence of hydrophobic compounds and the general penicillin susceptibility of genera making up the family Pasteurellaceae suggest a cell envelope having atypical permeability properties. The cell surface hydrophobicity properties of strains representing 15 of the 16 somatic serotypes of P. miltocida and three strains of ActinobaciUlus lignieresii were assessed with hydrocarbon adherence and hydrophobic interaction chromatographic assays. These methods revealed surface hydrophobicity to vary dramatically among strains in both species. No direct correlation was observed with species, growth rate, or susceptibility to the antibiotics oxytetracycline (polar), polymyxin B (amphiphilic), or novobiocin (nonpolar) as measured with MIC determinations. All strains were susceptible to the antibiotics, although A. lignieresii was significantly less susceptible than P. multocida to novobiocin. These data suggest that cell surface hydrophobicity in P. multocida may be influenced by the type of lipopolysaccharide present but is not directly related to permeability of the antibiotics examined. The wide diversity of hydrophobic properties exhibited by strains of both P. multocida and A. lignieresii precludes the use of this parameter as a taxonomic aid.

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Section: Resultssupporting

confidence: 91%

Variability of cell surface hydrophobicity among Pasteurella multocida somatic serotype and Actinobacillus lignieresii strains

Darnell¹,

Hart²,

Champlin³

1987

J Clin Microbiol

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“…Notable exceptions include Neisseria gonorrhoeae (22) and Legionella pneumophila (25), which have been'shown to be susceptible to hydrophobic compounds. The inability of P. multocida to grow on MacConkey agar (5), coupled with its high in vivo (13) and in vitro (7,9,13) permeability properties are likely due to anomalies in cell envelope chemical composition, because the organism exhibits otherwise typical gram-negative ultrastructure (3,31). Hydrophobic compounds are thought to penetrate bacterial membranes by diffusing through phospholipid bilayers in a nonspecific manner (26).…”

mentioning

confidence: 99%

Susceptibility to hydrophobic molecules and phospholipid composition in Pasteurella multocida and Actinobacillus lignieresii

Hart

Champlin

1988

Antimicrob Agents Chemother

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Despite its typically gram-negative cell envelope ultrastructure, Pasteurella multocida is susceptible to the hydrophobic antibiotic novobiocin and is unable to initiate growth on MacConkey agar, a parameter often used to effect its differentiation from other members of the family Pasteurellaceae such as Actinobacillus lignieresii. However, growth on basal medium supplemented with individual selective factors and an agar diffusion assay revealed the bile salts contained in MacConkey agar to be toxic to both organisms. Four P. multocida surface hydrophobicity variants exhibited consistent in vitro susceptibility to the hydrophobic antibiotics novobiocin, rifamycin SV, and actinomycin D as determined by broth dilution. Readily extractable lipid fractions were obtained by chloroform-methanol extraction of freeze-dried whole cells from exponential-phase cultures. No major differences in total cellular readily extractable lipid content were observed among the P. multocida and A. lignieresii stra,ins examined, although hydrophobic P. multocida strains appeared to contain slightly more than did hydrophilic strains. Analytical thin-layer chromatography and quantitation of resolved readily extractable lipid components revealed the major cell envelope phospholipids of both organisms to be phosphatidylethanolamine and phosphatidylglycerol in a molar ratio of approximately 4:1 regardless of cell surface hydrophobicity properties. Similar results were obtained for Pseudomonas aeruginosa, which is notably refractory to hydrophobic molecules. These data support the conclusion that the permeability of the P. multocida cell envelope to structurally unrelated, hydrophobic molecules is not dependent on cell surface hydrophobicity and cannot be explained on the basis of anomalous polar lipid composition.

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