Zoogloea oryzae sp. nov., a nitrogen-fixing bacterium isolated from rice paddy soil, and reclassification of the strain ATCC 19623 as Crabtreella saccharophila gen. nov., sp. nov

• Published in: International journal of systematic and evolutionary microbiology Vol. 56; no. 3; pp. 619 - 624
• Main Authors: Xie, Cheng-Hui, Yokota, Akira
• Format: Journal Article
• Language: English
• Published: Reading Soc General Microbiol 01.03.2006; Society for General Microbiology
• Subjects: Alphaproteobacteria - chemistry; Alphaproteobacteria - classification; Alphaproteobacteria - genetics; Alphaproteobacteria - isolation & purification; Bacteriology; Biological and medical sciences; DNA, Ribosomal - chemistry; Fatty Acids - analysis; Fundamental and applied biological sciences. Psychology; Microbiology; Miscellaneous; Nitrogen Fixation; Oryza - microbiology; Phylogeny; RNA, Ribosomal, 16S - genetics; Sequence Analysis, DNA; Soil Microbiology; Systematics; Zoogloea - chemistry; Zoogloea - classification; Zoogloea - genetics; Zoogloea - isolation & purification; Pseudomonadales; Taxonomic review; Soils; New genus; Taxonomy; Nitrogen fixation; Bacteria; Pseudomonadaceae; Zoogloea; Paddy field; Strain
• ISSN: 1466-5026; 1466-5034
• DOI: 10.1099/ijs.0.63755-0

Institute of Molecular and Cellular Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-Ku, Tokyo 113-0032, Japan Correspondence Cheng-Hui Xie aa37116{at}mail.ecc.u-tokyo.ac.jp Two strains of free-living diazotrophs isolated from soil from a rice paddy field were characterized by using a polyphasic approach. The novel strains, A-7 T and A-4, were found to be very closely related, with 99·9 % 16S rRNA gene sequence similarity and a DNA–DNA hybridization value of 89·5 %, suggesting that they represent a single species. 16S rRNA gene sequence analyses indicated that the two strains fell within the Zoogloea lineage, with less than 96·7 % sequence similarity to other Zoogloea species. Chemotaxonomic characteristics of the novel strains, including DNA G+C content (65·1 mol%), the major quinone system (Q-8), predominant fatty acids (16 : 1 7 c and 16 : 0) and major hydroxy fatty acids (3-OH 10 : 0 and 3-OH 12 : 0), are similar to those of the genus Zoogloea . The novel strains showed positive results for floc formation which is accepted as confirmatory for species of the genus Zoogloea . However, the novel strains can be distinguished from the other species of Zoogloea by physiological characteristics. The name Zoogloea oryzae sp. nov. is therefore proposed for the novel strains with strain A-7 T (=IAM 15218 T =CCTCC AB 2052005 T ) as the type strain. Phylogenetic and chemotaxonomic analyses indicate that strain ATCC 19623, designated as a reference strain of Zoogloea ramigera , does not belong to the genus Zoogloea but to a new genus of Alphaproteobacteria . The name Crabtreella saccharophila gen. nov., sp. nov. is proposed for strain ATCC 19623 T (=IAM 12669 T ). Abbreviations: PHB, poly- -hydroxybutyrate Published online ahead of print on 28 October 2005 as DOI 10.1099/ijs.0.63755-0. The GenBank/EMBL/DDBJ accession numbers for the 16S rRNA and nifH gene sequences of strains A-7 T and A-4 are AB201043 –AB201044 and AB201045 –AB201046, respectively. A phylogenetic tree based on nifH gene sequences and a table detailing the fatty acid content of the three Zoogloea species are available as supplementary material in IJSEM Online.