title: Isolation and Characterization of a New Methanobacterium formicicum KOR-1 from an Anaerobic Digester Using Pig Slurry.
abstract: A new methanogen was isolated from an anaerobic digester using pig slurry in South Korea. Only one strain, designated KOR-1, was characterized in detail. Cells of KOR-1 were straight or crooked rods, non-motile, 5 to 15 μm long and 0.7 μm wide. They stained Gram-positive and produced methane from H2+CO2 and formate. Strain KOR-1 grew optimally at 38°C. The optimum pH for growth was 7.0. The strain grew at 0.5% to 3.0% NaCl, with optimum growth at 2.5% NaCl. The G+C content of genomic DNA of strain KOR-1 was 41 mol%. The strain tolerated ampicillin, penicillin G, kanamycin and streptomycin but tetracycline inhibited cell growth. A large fragment of the 16S rRNA gene (~1,350 bp) was obtained from the isolate and sequenced. Comparison of 16S rRNA genes revealed that strain KOR-1 is related to Methanobacterium formicicum (98%, sequence similarity), Methanobacterium bryantii (95%) and Methanobacterium ivanovii (93%). Phylogenetic analysis of the deduced mcrA gene sequences confirmed the closest relative as based on mcrA gene sequence analysis was Methanobacterium formicicum strain (97% nucleic acid sequence identity). On the basis of physiological and phylogenetic characteristics, strain KOR-1 is proposed as a new strain within the genus Methanobacterium, Methanobacterium formicicum KOR-1.
authors.affiliation: Biogas Research Center, Hankyong National University, Anseong 456-749, Korea.
authors.forename: Urantulkhuur
authors.initials: U
authors.lastname: Battumur
authors.affiliation: Biogas Research Center, Hankyong National University, Anseong 456-749, Korea.
authors.forename: Young-Man
authors.initials: YM
authors.lastname: Yoon
authors.affiliation: Biogas Research Center, Hankyong National University, Anseong 456-749, Korea ; Department of Animal Life and Environment Science, Hankyong National University, Anseong 456-749, Korea.
authors.forename: Chang-Hyun
authors.initials: CH
authors.lastname: Kim
keywords: 16S rRNA; Anaerobic Digester; Methanobacterium formicicum; Methanogen; mcrA