title: Isolation of Inositol Hexaphosphate (IHP)-Degrading Bacteria from Arbuscular Mycorrhizal Fungal Hyphal Compartments Using a Modified Baiting Method Involving Alginate Beads Containing IHP.
abstract: Phytate (inositol hexaphosphate; IHP)-degrading microbes have been suggested to contribute to arbuscular mycorrhizal fungi (AMF)-mediated P transfer from IHP to plants; however, no IHP degrader involved in AMF-mediated P transfer has been isolated to date. We herein report the isolation of IHP-degrading bacteria using a modified baiting method. We applied alginate beads as carriers of IHP powder, and used them as recoverable IHP in the AM fungal compartment of plant cultivation experiments. P transfer from IHP in alginate beads via AMF was confirmed, and extracted DNA from alginate beads was analyzed by denaturing gradient gel electrophoresis targeting the 16S rRNA gene and a clone library method for the beta-propeller phytase (BPP) gene. The diversities of the 16S rRNA and BPP genes of microbes growing on IHP beads were simple and those of Sphingomonas spp. and Caulobacter spp. dominated. A total of 187 IHP-utilizing bacteria were isolated and identified, and they were consistent with the results of DNA analysis. Furthermore, some isolated Sphingomonas spp. and Caulobacter sp. showed IHP-degrading activity. Therefore, we successfully isolated dominant IHP-degrading bacteria from IHP in an AMF hyphal compartment. These strains may contribute to P transfer from IHP via AMF.
authors.affiliation: Graduate School of Agricultural Science, Tohoku University.
authors.forename: Shintaro
authors.initials: S
authors.lastname: Hara
authors.forename: Masanori
authors.initials: M
authors.lastname: Saito
mesh_terms: D010832:6-Phytase / Q000235:genetics; D000464:Alginates; D001419:Bacteria / Q000302:isolation & purification* / Q000378:metabolism*; D001431:Bacteriological Techniques / Q000379:methods; D001672:Biocompatible Materials; D044822:Biodiversity; D001711:Biotransformation; D016934:Caulobacter; D016000:Cluster Analysis; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D058645:Denaturing Gradient Gel Electrophoresis; D020723:Glucuronic Acid; D006603:Hexuronic Acids; D038821:Mycorrhizae; D010802:Phylogeny; D010833:Phytic Acid / Q000378:metabolism*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D020578:Sphingomonas
chemical_list: D000464:Alginates; D001672:Biocompatible Materials; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D006603:Hexuronic Acids; D012336:RNA, Ribosomal, 16S; D010833:Phytic Acid; D020723:Glucuronic Acid; D010832:6-Phytase