Journal article

Publication year: 1997

Pages: 89-97

Journal: Journal of Microbiological Methods

Volume number: 28

Issue number: 2

ISSN: 0167-7012

DOI Link: https://doi.org/10.1016/S0167-7012(96)00969-4

Publisher: Elsevier

Abstract: 

A total of 30 genotypically-characterized Aeromonas strains, encompassing DNA hybridization groups (HGs) 1, 2, 3 (A. hydrophila), 4, 5A (A. caviae), and 8 (A. veronii biogroup sobria), were cultivated on two different media, nutrient-rich trypticase soy agar (TSA) and nutrient-poor R2A medium, and their fatty acid methyl esters (FAMEs) were analyzed using an automated gas–liquid chromatographic system. A comparison of the respective HG-specific FAME compositions revealed that the difference in nutritional value of both media induced a pronounced quantitative effect on the overall branched-chain fatty acid (BFA) content. Strains grown on TSA medium generally produced significant amounts of the BFAs 13:0 iso, 15:0 iso, 15:0 iso 3OH, iso 17:1 ω9c, and 17:0 iso, whereas these BFAs were detected in much lower concentrations or even were absent in R2A cultures. To compensate for this depletion, strains cultivated on R2A agar produced higher amounts of the major fatty acids 16:1 ω7c and 16:0. The consequences of the observed medium-dependent shift in fatty acid production for the chemotaxonomic differentiation of HGs in Aeromonas were determined by constructing a similarity matrix from the mean FAME library entries and by multivariate grouping via principal components analysis. Results obtained from both mathematical approaches clearly demonstrated a higher resolving power of the TSA medium for the distinction of the six Aeromonas HGs examined in this study. In conclusion, when a standardized FAME protocol needs to be designed for taxonomic purposes, we recommend a thorough evaluation of the influence of the growth medium on bacterial fatty acid composition.

Harvard Citation style: Huys, G., Kämpfer, P., Vancanneyt, M., Coopman, R., Janssen, P. and Kersters, K. (1997) Effect of the growth medium on the cellular fatty acid composition of aeromonads: Consequences for the chemotaxonomic differentiation of DNA hybridization groups in the genus Aeromonas, Journal of Microbiological Methods, 28(2), pp. 89-97. https://doi.org/10.1016/S0167-7012(96)00969-4

APA Citation style: Huys, G., Kämpfer, P., Vancanneyt, M., Coopman, R., Janssen, P., & Kersters, K. (1997). Effect of the growth medium on the cellular fatty acid composition of aeromonads: Consequences for the chemotaxonomic differentiation of DNA hybridization groups in the genus Aeromonas. Journal of Microbiological Methods. 28(2), 89-97. https://doi.org/10.1016/S0167-7012(96)00969-4