title: Isolation and identification of methylobacterium species from the tap water in hospitals in Japan and their antibiotic susceptibility.
abstract: Contamination of tap water by Methylobacterium species has become a serious concern in hospitals. This study was planned to examine the distribution of Methylobacterium species inhabiting tap water used in Japanese hospitals and antibiotic sensitivity of the isolates in 2004. Species identification of 58 isolates was performed based on the homology of a partial sequence of 16S rDNA. The dominant Methylobacterium species in hospital water were M. aquaticum and M. fujisawaense. To examine the biochemical properties of these isolates, a carbon source utilization was tested using an API50CH kit. The phenotypic character varied widely, and was not necessarily consistent with the results of phylogenic analysis based on the partial 16S rDNA sequence, suggesting that the biochemical properties are not suitable for identification of Methylobacterium species. The isolates were also subjected to antibiotic sensitivity tests. They were resistant to 8 antibiotics, but highly sensitive to imipenem (MIC90 = 1 microg/ml) and tetracycline (MIC90 = 8 microg/ml). These findings concerning the isolates revealed the presence of Methylobacterium species with resistance to multiple antibiotics in hospital tap water.
authors.affiliation: College of Environmental Health, Azabu University, Sagamihara, Kanagawa 229-8501, Japan. furuhata@azabu-u.ac.jp
authors.forename: Katsunori
authors.initials: K
authors.lastname: Furuhata
authors.forename: Yuko
authors.initials: Y
authors.lastname: Kato
authors.forename: Keiichi
authors.initials: K
authors.lastname: Goto
authors.forename: Motonobu
authors.initials: M
authors.lastname: Hara
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Yoshida
authors.forename: Masafumi
authors.initials: M
authors.lastname: Fukuyama
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D015373:Bacterial Typing Techniques; D050260:Carbohydrate Metabolism; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D024881:Drug Resistance, Bacterial; D006761:Hospitals; D015378:Imipenem / Q000494:pharmacology; D007564:Japan; D020580:Methylobacterium / Q000145:classification / Q000187:drug effects* / Q000302:isolation & purification*; D008826:Microbial Sensitivity Tests; D010802:Phylogeny; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid; D013752:Tetracycline / Q000494:pharmacology; D014871:Water Microbiology; D014876:Water Pollution; D014881:Water Supply
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D015378:Imipenem; D013752:Tetracycline