%0 Journal Article %A Caudales, Rodulio %A Wells, John M. %A Antoine, Alan D. %T Cellular fatty acid composition of symbiotic cyanobacteria isolated from the aquatic fern Azolla %D 1992 %J Microbiology, %V 138 %N 7 %P 1489-1494 %@ 1465-2080 %R https://doi.org/10.1099/00221287-138-7-1489 %I Microbiology Society, %X The cellular fatty acid composition of 10 isolates of symbiotic cyanobacteria from 7 different species of the aquatic fern Azolla was investigated. Sixteen major components accounted for 88.31% of total fatty acids: the saturated 14:0, 16:0 and 18:0 carbon chains; the unsaturated straight-chained 12:1, 14:1 cis-7, 16:1 cis-7, 16:1 cis-9, 16:1 cis-11, 18:2 cis-9, 18:3 cis-9, 18:1 cis-and trans-9, and 20:4 cis-5; and the branch-chained iso-16:0. Also included was an unsaturated 16-carbon (equivalent carbon chain length of 15.5), with unsaturation sites undetermined. The most abundant component was the 16:0 (mean of 38.10% of the total). Thirty-six minor fatty acids, comprising 10.30% of the total, were detected and identified. These included hydroxy-substituted fatty acids (1.10%), branched chains in addition to the iso-16:0 (1.96% of a class total of 2.96%) and cyclopropane fatty acids (0.89%). A comparison of the fatty acid profile of Azolla cyanobionts with those previously published for free-living cyanobacteria of the genera Anabaena and Nostoc indicated that there were at least 19 individual fatty acids, class totals or ratios that were statistically different and could be used as differentiating factors. Nine of the 19 factors were characteristically unique to Azolla cyanobionts and different from both Anabaena and Nostoc. Five were different from only Anabaena, and five from only Nostoc. Based on one taxonomic interpretation of fatty acid analysis, the Azolla cyanobionts appeared to be equally distinct from Anabaena and from Nostoc. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-138-7-1489