The use of a flexible, fused-silica capillary column for gas-liquid chromatographic analysis of bacterial fatty acids is illustrated with Propionibacterium acnes, Propionibacterium shermanii, and a standard methyl ester mixture. Determination of bacterial fatty acid compo-done on glass columns of varying lengths, with sition by gas-liquid chromatography (GLC) has internal diameters generally from 2 to 4 mm, proved to be a valuable additional means for packed with polar or nonpolar stationary-phase rapid identification of a variety of bacteria (2, 4, materials (4). Not all of the acids in a complex 6, 10). Recent examples in this laboratory are bacterial mixture, however, are separated on Legionella pneumophila and some Legionellapacked columns, and some appear as shoulders like organisms (1, 5, 9). In general, the GLC on the leading or trailing edge of other peaks in analysis of fatty acids (as methyl ester) has been the GLC chromatogram (4). Increased separa-P.d* No. Idetity

Seven strains of Flavobacterium thalpophilum which were isolated from clinical sources were compared with the type strains of Sphingobacterium mizutae and seven species of Flavobacterium. These 15 strains were examined for 11 biochemical characteristics; minor phenotypic variations were observed for the 7 strains of F. thalpophilum. All 15 strains were characterized by four major cellular fatty acids (13-methyltetradecanoate, 2-hydroxy-13-methyltetradecanoate, 3-hydroxy-15-methylhexadecanoate, and a monounsaturated 16-carbon straight-chain acid). Sphingophospholipid long-chain bases were detected in all strains of F. thalpophilum but were not detected in Flavobacterium balustinum, Flavobacterium breve, Flavobacterium indologenes, Flavobacterium meningosepticum, or Flavobacterium odoratum. F. thalpophilum, Flavobacterium multivorum, Flavobacterium spiritivorum, and S . mizuate contained major amounts of menaquinone 7 but no menaquinone 6, whereas F . balustinum, F. breve, F. indologenes, F. meningosepticum, and F. odoratum contained major amounts of menaquinone 6 but no menaquinone 7. The phenotypic and chemical characteristics of F. thalpophilum indicate a close taxonomic relationship with F. multivorum, F. spiritivorum, and S . mizutae.Recently, a new species of Flavobacterium, Flavobacterium thalpophilum, was described by Holmes et al. (10). The strains comprising this species were gram-negative, yellowpigmented, aerobic, nonsporeforming , nitrate-reducing , nonmotile rods which grew at 37 and 42°C. The guanine-pluscytosine G+C contents of the deoxyribonucleic acids (DNAs) of these strains were 45.0 t 0.8 mol% (lo), whereas all previously recognized Flavobacterium species had G + C contents between 31 and 42 mol% (1&13). Phenotypic characteristics and DNA-DNA relatedness studies showed that the F. thalpophilum strains constituted a single species (10). However, the phenotypic characteristics were too similar to those of existing Flavobacterium species to warrant creation of a new genus. Thus, to include F. thalpophilum in the genus Flavobacterium, Holmes et al. expanded the upper limit of the G+C content range of the genus to approximately 46 mol% (10).Before F. thalpophilum was described, Yabuuchi et al. (26) proposed the genus Sphingobacterium for two species of Flavobacterium (Flavobacterium multivorum and Flavobacterium spiritivorum) and a newly recognized species (Sphingobacterium mizutae). All of the strains examined contained sphingophospholipids and had G+ C contents of approximately 40 to 42 mol% (10,26,29). Phenotypic characteristics and DNA-DNA relatedness studies separated these strains into three species, each of which was distinct from other flavobacteria. Although all three sphingobacteria had G+C contents within the range described for previously recognized Flavobacterium species, generic assignments were based predominantly on the presence of relatively large concentrations of sphingophospholipids.In this investigation, we compared the phenotypic characteristics and isoprenoid quinone , sphi...

The cellular fatty acid, sphingolipid, and isoprenoid quinone compositions of Flavobactenium odoratum, Flavobactenium breve, and Flavobacterium-like groups Ile, IIh, and Ilf were determined, using thin-layer, gas-liquid, and reverse-phase high-performance liquid chromatography. The fatty acid data showed that groups Ile, IIh, and lIf were similar to recognized Flavobacterium species by the presence of relatively large amounts of iso-branched hydroxy and nonhydroxy acids. Groups Ile and IIh were essentially identical in fatty acid composition but were distinguished from group IIf, F. breve, and F. odoratum on the basis of minor qualitative and quantitative differences. All strains tested contained menaquinone 6 as the major isoprenoid quinone, and all lacked sphingolipids. Overall, the chemical data suggest that groups Ile, IIh, and Ilf are additional Flavobacterium species and are different from sphingobacteria, which contain sphingolipid and menaquinone 7 as the major quinone.

The cellular fatty acid composition of 25 clinical isolates of Alcaligenes and Pseudomonas was determined by gas-liquid chromatography (GLC). The GLC fatty acid profiles of three species of Pseudomonas were markedly different from those of Alcaligenes. The most significant differences were the presence and relative amounts of hydroxy, branched-chain, and cyclopropane fatty acids. One of the major fatty acids in A. faecalis was a 17-carbon cyclopropane (17 delta) acid, whereas a 15-carbon branched-chain acid (13-methyl tetradecanoate) characterized isolates of P. putrefaciens. The determination of these fatty acids by GLC provides a rapid and specific means of distinguishing clinical isolates of Pseudomonas and Alcaligenes.

The cellular fatty acid composition of a group of gram-negative nonfermentative organisms designated group IVe was studied by gas-liquid chromatography. Strains of this group are isolated most frequently from urine and most closely resemble the Alcaligenes in conventional biochemical tests. On the basis of cellular fatty acids, however, we found these organisms to be strikingly different from Alcaligenes and other gram-negative species with similar phenotypic characteristics. The gas-liquid chromatography procedure offers an additional diagnostic test for rapid identification of unclassified bacteria like group IVe.