- Volume 44, Issue 2, 1994

Cellular fatty acid profiles were determined for species in 33 genera of anaerobic gram-negative bacilli and were confirmed to be a useful taxonomic tool. Most of the genera could be differentiated by visual inspection of their profiles. The three genus pairs that were most difficult to distinguish visually (Bacteroides and Prevotella, Pectinatus and Megamonas, and Serpulina and Bilophila) and the species of these genera were differentiated by the MIDI (Microbial ID, Inc.) identification system. Similarities in cellular fatty acid profiles may be correlated with similarities in other phenotypic characteristics, but more often there is no other obvious phenotypic relationship. Although medium components may not change the constituents detected or the ratios among the constituents detected for some species, identical medium changes may result in vast differences in the profiles obtained with other species. Thus, if a worker wishes to compare profiles of various taxa, it is essential that the same cultural and analytical conditions be used.

A new gram-positive, nonmotile coccus is described. Strains IFO 12422T (T = type strain) and IFO 15385 in the Institute for Fermentation, Osaka, culture collection, which were isolated from soil and water, respectively, have the following chemotaxonomic characteristics: menaquinone MK-9(H4); G+C content of DNA of 67 mol%; and LL-diaminopimelic acid, alanine, glycine, and glutamic acid in a molar ratio of ca. 1:2:1:1 (type Α3γ). Mycolic acids are not present. The taxonomic characteristics of these organisms are different from those of previously described gram-positive, high-G+C-content cocci. The partial 16S rRNA sequence indicated that IFO 12422T represents a distinct line of descent among gram-positive bacteria with a high G+C content. The name Luteococcus japonicus gen. nov., sp. nov. is proposed. The type strain is strain IFO 12422.

A sequence analysis of the 16S rRNA of Methanolobus siciliae T4/MT (T = type strain) showed that this strain is closely related to members of the genus Methanosarcina, especially Methanosarcina acetivorans C2AT. Methanolobus siciliae T4/MT and HI350 were morphologically more similar to members of the genus Methanosarcina than to members of the genus Methanolobus in that they both formed massive cell aggregates with pseudosarcinae. Thus, we propose that Methanolobus siciliae should be transferred to the genus Methanosarcina as Methanosarcina siciliae.

The results of phylogenetic analysis in which 16S ribosomal DNA sequences were compared confirmed previous chemotaxonomic data which suggested that Paracoccus halodentrificans is inappropriately placed in the genus Paracoccus, which belongs in the a subclass of the Proteobacteria. P. halodenitrificans should be placed in the family Halomonadaceae, which belongs in the y subclass of the Proteobacteria.

Pulsed-field gel electrophoresis (PFGE) studies performed with leptospiral isolates led us to suspect the existence of a new serovar in the Grippotyphosa serogroup. The results obtained with reference serological techniques used in leptospiral identification, including cross-agglutination absorption and monoclonal antibody techniques, confirmed the existence of a new serovar exemplified by strain Dadas I. Four other isolates from different regions of the world were submitted for identification by PFGE and produced NotI restriction patterns similar to that of strain Dadas I. Our data demonstrate the power of PFGE for identifying leptospiral isolates. The name dadas is proposed for the new serovar.

The 16S rRNA gene sequence of Melissococcus pluton, the causative agent of European foulbrood disease, was determined in order to investigate the phylogenetic relationships between this organism and other low-G+C- content gram-positive bacteria. A comparative sequence analysis revealed that M. pluton is a close phylogenetic relative of the genus Enterococcus.

Arthroascus fermentans, a new arthrosporous, fermenting, ascogenous yeast species, is described. The three strains of the species included in this study were isolated from soil samples obtained from different orchards in Taiwan. The species is homothallic, and the major ubiquinone isoprenolog is Q-8. DNA hybridization and DNA base composition data indicate that A. fermentans is a species that is distinct from previously described Arthroascus species. The type strain of A. fermentans is strain 80D2303, which has been deposited in the Culture Collection and Research Center, Food Industry Research and Development Institute, Hsinchu, Taiwan, as strain CCRC 22530.