Plesiocystis pacifica gen. nov., sp. nov., a marine myxobacterium that contains dihydrogenated menaquinone, isolated from the Pacific coasts of Japan Two strains of a novel myxobacterium (designated SIR-1 T and SHI-1) were isolated from Japanese coasts located in the Pacific subtropical zone. Cells of both strains were Gram-negative, rodshaped and motile by gliding. The strains were chemoheterotrophic and strictly aerobic. They had the common characteristics associated with myxobacteria, such as bacteriolytic action and fruitingbody formation. The characteristic feature of the strains was a NaCl growth requirement with an optimum concentration of 2?0-3?0 % (w/v), comparable to that of sea water. In addition, other cationic components of sea water, such as Mg 2+ , Ca 2+ and K + , were needed for growth. The major respiratory quinone was MK-8(H 2 ). The cellular fatty acid profile was characterized by the predominance of iso-C 15 : 0 . Characteristic fatty acids anteiso-C 16 : 0 and anteiso-C 17 : 0 , and a long-chain polyunsaturated fatty acid (C 20 : 4 ), were also detected. The G+C content of the genomic DNA of strains SIR-1 T and SHI-1 was between 69?3 and 70?0 mol% (as determined by HPLC). Strains SIR-1 T and SHI-1 shared almost identical 16S rDNA sequences, and clustered with the genus Nannocystis as their closest relative upon phylogenetic analysis. However, the phylogenetic distance between the novel strains and the genus Nannocystis was large enough to warrant their different generic allocation. This finding was supported by significant phenotypic differences between the novel strains and Nannocystis. Thus, strains SIR-1 T and SHI-1 represent a novel genus and species, for which the names Plesiocystis and Plesiocystis pacifica, respectively, are proposed. The type strain of the species is SIR-1 T (=JCM 11591 T =DSM 14875 T =AJ 13960 T ). INTRODUCTIONThe myxobacteria are Gram-negative, rod-shaped, gliding bacteria with a high G+C content. One unique characteristic of myxobacteria is a process of intercellular development that leads to fruiting-body formation. Morphological features of fruiting bodies have been regarded as a key criterion for the classification of this group of bacteria (McCurdy, 1989;Reichenbach, 1993). 16S rDNA sequence studies have revealed that they form a relatively homogeneous cluster within the d-Proteobacteria (Shimkets & Woese, 1992; Spröer et al., 1999).Abbreviation: PUFA, polyunsaturated fatty acid.

The growth‐inhibitory activity of Galla Rhois‐derived materials towards 17 intestinal bacteria was evaluated using an impregnated paper disc method. The biologically active components of Galla Rhois were characterized as the tannins methyl gallate (MG) and gallic acid (GA) by spectral analysis. The growth responses varied with bacterial strain tested. In the test using 10 mg disc−1, MG and GA produced a clear inhibitory effect on harmful bacteria such as Clostridium perfringens, Cl. paraputrificum, Eubacterium limosum, Bacteroides fragilis, Staphylococcus aureus and Escherichia coli. Methyl gallate showed no growth‐inhibitory activity towards Bifidobacterium adolescentis or B. longum whereas the growth of B. bifidum, B. breve, B. infantis, B. animalis, B. thermophilum, Lactobacillus acidophilus, Lact. plantarum and Streptococcus faecalis was slightly affected. However, GA did not adversely affect the growth of the bifidobacteria and lactobacilli. At 5 mg disc−1, MG significantly inhibited the growth of Cl. perfringens and Cl. paraputrificum but did not affect the growth of the bifidobacteria and lactobacilli. At 1 mg disc−1, MG greatly inhibited the growth of Cl. perfringens alone. These results may be an indication of at least one of the pharmacological actions of Galla Rhois.

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