Methylobacterium oryzae sp nov., an aerobic, pink-pigmented, facultatively methylotrophic, 1-aminocyclopropane-L-carboxylate deaminase-producing bacterium isolated from rice

A pink-pigmented, facultatively methylotrophic bacterium, strain CBMB20(T), isolated from stem tissues of rice, was analysed by a polyphasic approach. Strain CBMB20(T) utilized 1 anninocyclopropane 1-carboxylate (ACC) as a nitrogen source and produced ACC deaminase. It was related phylogenetically to members of the genus Methylobacterium. 16S rRNA gene sequence analysis indicated that strain CBM1320(T) was most closely related to Methylobacterium fujisawaense, Methylobacterium radiotolerans and Methylobacterium mesophilicum; however, DNA-DNA hybridization values were less than 70 % with the type strains of these species. The DNA G + C content of strain CBM1320(T) was 70.6 mol%. The study presents a detailed phenotypic characterization of strain CBMB20(T) that allows its differentiation from other Methylobacterium species. In addition, strain CBMB20(T) is the only known member of the genus Methylobacterium to be described from the phyllosphere of rice. Based on the data presented, strain CBMB2(T) represents a novel species in the genus Methylobacterium, for which the name Methylobacterium oryzae sp. nov. is proposed, with strain CBM132(T) (=DSM 18207(T)=LMG 23582(T)=KACC 11585(T)) as the type strain.