title: [A novel plant-associated thermotolerant alkalophilic methylotroph of the genus Paracoccus].
abstract: Strain GB isolated from the maize rhizosphere is a gram-negative, aerobic, non-spore-forming, nonpigmented, nonmotile, chemolithotrophic, facultatively methylotrophic bacterium. Cells are cocci or short rods. The strain does not require vitamins. Optimum growth in a medium with methanol occurs at 38-42 degrees C at pH 8.0-9.2. The doubling time is 12 h. In addition to methanol, the bacterium can grow on methylamine, dimethylformamide, acetone, thiosulfate + NaHCO3, and in an atmosphere of H2 + CO2 + O2. Methanol and methylamine are oxidized by the respective dehydrogenases to CO2 via formaldehyde and formate, respectively. The CO2 produced is assimilated via the ribulose bisphosphate pathway. Fatty acids are dominated by cyclopropanoic (58-61%), palmitic (24-26%), and octadecanoic (8-9%) acids. The main phospholipids are phosphatidylglycerol, phosphatidylethanolamine, and phosphatidylcholine. The major ubiquinone is Q10. The bacterial genome contains genes controlling the synthesis and secretion of cytokinins. The culture liquid exhibits cytokinin activity. The G + C content of DNA is 62.5 mol %, as determined from the DNA thermal denaturation temperature (Tm). Strain GB shows a moderate degree of DNA-DNA homology (< 40%) with the type representatives of the genus Paracoccus. Based on the data obtained, the bacterium was classified as a new species of this genus, named P. kondratievae.
authors.affiliation: Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, pr. Nauki 5, Pushchino, Moscow oblast, 142290 Russia.
authors.forename: N V
authors.initials: NV
authors.lastname: Doronina
authors.forename: Iu A
authors.initials: IuA
authors.lastname: Trotsenko
mesh_terms: D000432:Methanol / Q000378:metabolism; D010230:Paracoccus / Q000302:isolation & purification* / Q000502:physiology*; D013696:Temperature; D003313:Zea mays / Q000382:microbiology
chemical_list: D000432:Methanol