Occurrence of isoprenoid compounds in gram-negative methanol-, methane-, and methylamine-utilizing bacteria.

Abstract

The isoprenoid compounds in gram-negative methanol-, methane-, and methylamine-utilizing bacteria were investigated. All strains tested contained ubiquinone, but none contained menaquinone. The ubiquinone types were Q-8, Q-9, or Q-10. The so-called obligate methylotrophs and methanotrophs (genus Methylobacillus, Methylophaga, Methylomonas, Methylococcus, and Methylovibrio) contained ubiquinone Q-8. The Hyphomicrobium strains contained Q-9. The other facultative methylotrophs and methylamine-utilizing bacteria contained Q-10. A large amount of squalene occurred in the Methylobacillus, Methylophaga, Methylomonas, and Methylococcus strains which utilize one-carbon compounds via the ribulose monophosphate pathway. The Pro tomonas extorquens and Methylobacterium organophilum strains contained a large amount of sterols , carotenoid pigments, and a small amount of squalene. The Hyphomicrobium strains contained a small amount of squalene and Hop-22(29)-ene. The Xanthobacter strains contained a large amount of carotenoid pigments (zeaxanthin, zeaxanthin monorhamnoside, and zeaxanthin dirhamnoside). The Protomonas and Methylobacterium strains were unique in the existence of sterols and large amounts of total isoprenoid compounds, 4.68 to 7.97 mg/g of dry cell. The distribution of squalene, sterols, quinones, and carotenoid pigments conforms with the morphological, physiological, and other chemotaxonomic characteristics in gram-negative methanol-, methane-, and methylamine-utilizing bacteria. The ubiquinone, menaquinone, squalene, sterols, and carotenoid pigments contained in bacterial cells are known as isoprenoid compounds. The taxonomic significance of ubiquinone and menaquinone in the classification of bacteria has been pointed out (1-3). On the other hand, until 1967, squalene and sterols had been encountered only in eukaryotic organisms, and not in prokaryotic organisms, bacteria and blue-green algae (4). In recent years, sterols and the sterol precursor, squalene, have been detected in Azotobacter chrococcum (5), Staphylococcus aureus (6, 7), Halobacterium cutirubrum (8), Methylococcus capsulatus (9,10), Bacillus acidocaldarius (I1), and Acetobacter xylinum (12), and methanol-utilizing bacteria such as Methylobacterium organophilum (13), Pseudomonas sp. C (14), "Pseudomonas methylotropha" (14), "Methylomonas me thanolica" (14), Pseudomonas sp. C45 (15), Pseudomonas AM-1(15), Pseudomonas M27 (15), and "Protaminobacter ruber" (15).In this paper, we describe the distribution of ubiquinone, squalene, sterols, and carotenoid pigments in gram-negative bacteria that use methanol, methane, and methylamine. The significance of these isoprenoid compounds is discussed with regard to the classification of bacteria. MATERIALS AND METHODSBacterial strains. The strains studied and other strain designations are listed in Table 1. In addition to the bacteria described previously (16-24), bacteria closely related to gram-negative methanol-, methane-, and methylamine-utilizing bacteria were included in this study. The methanol-utilizi...

Characterization of Species of Marine Methylotrophs of the Genus Methylophaga

“…Based on these data, Janvier et al (7) established a new genus, Methylophaga. Our data on DNA base compositions, quinone systems (22), and cellular fatty acid profiles verify the establishment of this genus for these marine methanolutilizing bacteria.…”

“…Their DNA composition ranges from 43 to 49 mol% G+C. The homogeneity of these strains was supported by their cellular fatty acid compositions, their quinone systems (22), and the occurrence of squalene (22). Obligately C1-utilizing bacteria that use the RuMP pathway have been described for marine methanol-utilizing bacteria, methanol-utilizing bacteria (Methylobacillus strains), and methane-utilizing bacteria (Methylomonas and Methylococcus strains).…”

“…We believe that these bacteria consist of the following four major groups, based on a combination of characteristics (utilization of methane or methanol, ultrastructure of cells, and chemotaxonomic and biochemical data): (i) Methylobacillus strains that are unable to utilize methane (the group 1 methanol-utilizing bacteria that we described previously [17, 18, 21, 23, 311); (ii) Methylophaga strains that are unable to utilize methane (the group 11 methanol-utilizing bacteria that we described previously (7, 22, 23); (iii) Methylomonas strains (the group 1 methane-utilizing bacteria that we described previously (19,22,26); and (iv) Methylococcus strains (the group 2 methane-utilizing bacteria that we described previously (22, 26).…”

Further Studies of the Genus Methylobacterium and Description of Methylobacterium aminovorans sp. nov.

“…Carotenoid and bacteriochlorophyll pigments were detected by the method described previously (41,43 TK 0021 TK 0022 TK 0023 TK 0024 TK 0025 TK 0027T TK 0028T TK 0029 TK 0034T TK 0035 TK 0036T TK 0037 TK 0038 TK 0039 TK 0040 TK 0042 TK 0043 TK 0044 TK 0045 TK 0047T TK 0048 TK 0065T TK 0066 TK 0067 TK 0068 TK 0069 TH-lST NCIB 9399T, JCM 2802T NCIB 10409, JCM Phospholipid composition. Lipids were extracted by the procedure of Bligh and Dyer (3).…”

“…Quinone systems were determined as described previously (43). In the designations used for ubiquinones, the number indicates the number of isoprenoid units in the side chain (e.g., ubiquinone 9, ubiquinone 10, etc.…”