Affiliation:
1. Department of Microbiology and Immunology, University of Oregon Health Sciences Center, Portland, Oregon 97201
Abstract
Fatty acids of various chain lengths (C
1
to C
24
) were examined for their effects on growth, oxygen consumption, and in vitro reduced nicotinamide adenine dinucleotide oxidase activity of
Neisseria gonorrhoeae
CS-7. The growth inhibition caused by saturated fatty acids increased with increasing chain length to a maximum with palmitic acid (C
16
). Stearic acid (C
18
) and longer saturated fatty acids showed little inhibition of growth. However, unsaturated fatty acids of chain length C
16
to C
20
were inhibitory. Similar inhibition was observed with
Bacillus subtilis
and a deep rough mutant of
Salmonella typhimurium.
Wildtype
S. typhimurium
and
Pseudomonas aeruginosa
were more resistant to medium-chain (C
7
to C
10
) fatty acids and completely resistant to long-chain (C
12
to C
18
) fatty acids. Thus, sensitivity of
N. gonorrhoeae
to long-chain fatty acids appears to be related to the permeability of the outer membrane. Growth inhibition by short-chain (C
1
to C
6
) fatty acids was pH dependent; inhibition of growth increased with decreasing pH. Saturated fatty acids inhibited oxygen consumption by log-phase cells of
N. gonorrhoeae.
This inhibition increased with increasing chain length to a maximum observed with myristic acid (C
14
). Whereas stearic acid (C
18
) had little effect upon oxygen consumption, unsaturated C
18
fatty acids were inhibitory. An in vitro inhibition of reduced nicotinamide adenine dinucleotide oxidase activity by saturated (C
1
to C
12
) and unsaturated (C
16
to C
20
) fatty acids was also observed. Although the inhibitory concentrations were generally higher than those required to inhibit growth or oxygen consumption, an inhibition of electron transport may be partially responsible for the observed growth inhibition.
Publisher
American Society for Microbiology
Subject
Infectious Diseases,Immunology,Microbiology,Parasitology
Reference50 articles.
1. Uncoupling activity of long-chain fatty acids;Borst P.;Biochim. Biophys. Acta,1962
2. Inhibition of phosphate and arsenate uptake in yeast by monoiodoacetate, fluoride, 2,4-dinitrophenol and acetate;Borst-Pauwels G. W. F. H.;Biochim. Biophys. Acta,1969
3. Analysis by gas chromatography of fatty acids found in whole cultural extracts of Neisseria species;Brooks J. B.;Can. J. Microbiol.,1971
4. Potassium acetate inhibition of Lactobacillus casei and its reversal by lithium, sodium, and fatty acids;Camien M. N.;Proc. Soc. Exp. Biol. Med.,1957
5. Further observations on the relation ofpH value to toxicity of preservatives to microorganisms;Cruess W. V.;J. Bacteriol.,1932