RESUMEN
Twenty-three nitrogen-fixing bacteria were isolated from surface-sterilized stems and roots of wild rice Oryza rufipogon. Four clusters were defined among these bacteria by SDS-PAGE protein patterns and further confirmed by IS-PCR finger-printing analysis. Phylogenetic analysis of 16S rRNA gene sequences showed that the representative strains LS 8 and LS 18 of cluster II formed a monophyletic group sharing 94.0-97.3% similarities with defined enterobacterial species within the genera Salmonella, Citrobacter, Pantoea, Klebsiella, and Enterobacter. DNA-DNA hybridization, physiological, biochemical tests, and cell morphology also revealed that these strains could be differentiated from the related enterobacterial species. Based upon these results, we propose Phytobacter diazotrophicus gen. nov., sp. nov. to the bacterial group represented by strains LS 8 and LS 18. The type strain is LS 8(T) (=DSM 17806(T) = LMG 23328(T) = CGMCC 1.5339(T)). The DNA G+C content of strain LS 8(T) is 58.6 +/- 0.5 mol%.
Asunto(s)
Enterobacteriaceae/aislamiento & purificación , Fijación del Nitrógeno , Oryza/microbiología , Secuencia de Bases , Dermatoglifia del ADN , Electroforesis en Gel de Poliacrilamida , Enterobacteriaceae/clasificación , Enterobacteriaceae/ultraestructura , Datos de Secuencia Molecular , Oxidorreductasas/genética , Filogenia , Reacción en Cadena de la Polimerasa , ARN Bacteriano/genética , ARN Ribosómico 16S/genéticaRESUMEN
OBJECTIVE: To study the epidemic situation and dominant strain of influenza in children with acute respiratory infection (ARI) during Flu season from Oct. 2005 to Mar. 2006 in Taiyuan. METHODS: Madin-darby canine kidney (MDCK) cell culture and hemagglutination inhibition (HI) assay were used to isolate and identify type A influenza viruses (H1N1 and H3N2) and B influenza viruses from clinical samples collected from outpatients who visited the Department of Pediatric because of ARI from Oct. 2005 to Mar. 2006. Oct. 2005 and Mar. 2006, we collected 415 blood samples from children and adults to detect the influenza virus antibody titers by HI test to exclude respiratory diseases. RESULTS: 7 strains of H1N1 were isolated from 87 clinical specimens, with a positive rate of H1N1 as 8.04%. Out of 415 blood samples being collected, the positive rates and the geometric mean titer of H1N1 antibody Mar. 2006 were significantly higher in 0-3, 3-7 and 7-18 year-olds than Oct.2005. CONCLUSION: H1N1 epidemic influenza did occur among children in winter and spring of 2005--2006 in Taiyuan city.
Asunto(s)
Subtipo H1N1 del Virus de la Influenza A/aislamiento & purificación , Gripe Humana/epidemiología , Vigilancia de la Población , Adolescente , Animales , Anticuerpos Antivirales/sangre , Línea Celular , Niño , Preescolar , China/epidemiología , Perros , Pruebas de Inhibición de Hemaglutinación , Humanos , Lactante , Subtipo H3N2 del Virus de la Influenza A/aislamiento & purificación , Virus de la Influenza B/aislamiento & purificaciónRESUMEN
Eight fast-growing rhizobial isolates from Xinjiang soils were identified as Sinorhizobium xinjiangense by analyses of 16S rRNA gene sequences, SDS-PAGE of proteins, intergenic spacer sequences and DNA-DNA hybridization. Based on all of the results, these isolates and the reference strains for S. xinjiangense were a distinct genomic species, although the 16S rRNA genes were closely related to that of Sinorhizobium fredii.