Characteristics of Newly Isolated Xanthobacter Strains and Fatty Acid Compositions and Quinone Systems in Yellow-Pigmented Hydrogen-Oxidizing Bacteria

Abstract

Newly isolated Xanthobacter strains were characterized. In addition, the fatty acid compositions and quinone systems of gram-negative, yellow-pigmented, hydrogen-oxidizing bacteria belonging to the genera Xanthobacter, Hydrogenophaga, and Variovorax and related species were studied. Xanthobacter strains are nitrogen-fixing organisms that have a Q-10 ubiquinone system; the cellular fatty acids of these organisms include high levels of Cls,l acid, and their hydroxy fatty acids include high levels of 3-OH c16:o acid. Hydrogenophaga strains are polarly flagellated organisms that have a Q-S ubiquinone system. These bacteria can be divided into two groups on the basis of cellular fatty acid and hydroxy fatty acid compositions. Variovorax strains are peritrichously flagellated, non-nitrogen-fixing organisms that have a Q-S ubiquinone system; the cellular fatty acids of these strains include high levels of C16:o, c 1 6 : 1 and C18:. acids, and their hydroxy fatty acids include 3-OH CIo:o and 2-OH C14:o acids. Xanthobacter, Hydrogenophaga, and Variovorax strains can be clearly distinguished from each other on the basis of their quinone systems and cellular fatty acid compositions.Previously (28-31), we described a group of gram-negative methanol-utilizing bacteria on the basis of their morphological characteristics, utilization of carbon compounds, DNA base compositions, DNA-DNA hybridization data, cellular fatty acid compositions, ubiquinone systems. and enzyme electrophoretic properties. The group 5 bacteria that we described (29, 30) are nitrogen-fixing, hydrogen-oxidizing, non-sporeforming, gram-negative, rod-shaped, yellow-pigmented organisms that have a Q-10 ubiquinone system and cellular fatty acids that include high levels of Xanthobacter strains (22,35,38) are included in this group.Coiynebacterium autotrophicum (6) and "Mycobacterium jlavum" (= "Microbacterium flavum") (14, 23) were transferred to the new genus Xanthobacter as Xanthobacter autotrophicus and Xanthobacterflavus by Wiegel et al. (38) and Malik and Claus (22), respectively. In 1987, Xanthobacter agilis (1 8) was described as a third Xanthobacter species, and this species could be clearly distinguished from the two other Xanthobacter species on the basis of pleomorphism, motility, and colony color (2). X autotrophicus DSM 432T (T = type strain), DSM 431, DSM 685, DSM 1393 (= JCM 786l), DSM 1618 (= JCM 7862), DSM 2009 (= JCM 7863), and DSM 597 (= JCM 7864), X jlavus NCIB 1007T (= DSM 338'), and all of our isolates (strains BY-1, BY-3 to BY-11, and BY-15) were gram-negative, non-spore-forming, rod-shaped, methanol-utilizing organisms whose cells were 0.5 to 0.9 by 1.0 to 3.0 pm and had rounded ends. Nonmucoid yellow colonies were produced on PYG medium, nutrient medium, or methanol-containing me-

Acetate oxidation by syntrophic association between Geobacter sulfurreducens and a hydrogen-utilizing exoelectrogen

“…G. sulfurreducens strain PCA has menaquinone (MK)-8 as a main quinone, whereas Hydrogenophaga sp. strain AR20 has ubiquinone (UQ)-8 (Urakami et al, 1995;Mikoulinskaia et al, 2001).…”

Hydrogenophilus thermoluteolus gen. nov., sp. nov., a thermophilic, facultatively chemolithoautotrophic, hydrogen-oxidizing bacterium

“…Acidovorax delafieldii and Acidovorax facilis, which formerly belonged to the genus Pseudomonas, are facultatively hydrogen-oxidizing bacteria (Willems et al, 1990 chemolithoautotrophic, hydrogen-oxidizing bacterium (Aragno & Schlegel, 1992). Strains TH-lT and TH-4 are different from the genera Hydrogenophaga, Alcaligenes and Ralstonia in the terms of carbonsource utilization and major-fatty-acid composition (Aragno & Schlegel, 1992;Busse & Auling, 1992;Oyaizu-Masuchi & Komagata, 1988;Urakami et al, 1995;Willems et al, 1989). The phylogenetic positions of Hydrogenophaga, Alcaligenes and Ralstonia are quite different from those of strains TH-lT and TH-4 (Fig.…”

Phylogenetic relationships among members of the Comamonadaceae, and description of Delftia acidovorans (den Dooren de Jong 1926 and Tamaoka et al. 1987) gen. nov., comb. nov.

“…The following organic compounds can be utilized as carbon and energy sources : acetate, acetamide [reported as a variable reaction by Tamaoka et al ( 1 987) and Willems et al (1991b) De Vos et al (1985), Palleroni (1984), Tamaoka et al (1987) andWillems et al (1991b);b, De Vos et al (1985), Palleroni (1984), Tamaoka et al (1987) and Willems et al (1991b);c, Palleroni (1984) and Willems et al (1990Willems et al ( , 1992b; d, Palleroni (1984) and Willems et al (1989); e, Kersters & De Ley (1984), Urakami et al (1995) and Willems et al (1991a);h Bradbury (1984) and Willems et al (1987Willems et al ( , 1991a; g , Hiraishi et al (1991); h, Hiraishi et al (1995) -gens et al (1996);j, Hamana et al (1994), Krieg (1984), Pot et al (1992a, b) (199 1 b) analysis. The type strain is ATCC 15668T (den Dooren de Jong 7T; Stanier 14T; ACM 489T; LMG 1226T NCIB 968 1' ) .…”