RESUMEN
A novel yellow-pigmented, aerobic, rod-shaped, non-motile bacterium, designated strain CCMF41T, was isolated from rhizosphere soil of maize (Zea mays) collected in Wufeng District, Taichung, Taiwan. Strain CC-MF41T exhibited 16S rRNA gene sequence similarity of 97.5, 97.3, 97.2 and 97.1% to Leucobacter chironomi MM2LBT (and 'Leucobacter kyeonggiensis'F3-P9 and 'L. humi' Re-6, the names of which have not been validly published), Leucobactertardus K70/01T, L. komagatae IFO 15245T and 'Leucobacter margaritiformis' A23. However,CC-MF41T and 'L. margaritiformis' A23 formed a loosely bound phylogenetic lineage (with alow bootstrap value) associated with species of the genus Leucobacter. In DNADNA reassociation experiments, the relatedness of strain CC-MF41T to L. chironomi DSM 19883T was 57.1% (reciprocal value 29.1 %). The DNA G+C content of strain CC-MF41T was 72.1 mol% and the cell-wall peptidoglycan contained 2,4-diaminobutyric acid, alanine, glycine,glutamic acid and threonine. The major menaquinone was MK-11 and the predominant fatty acids were iso-C16 : 0, anteiso-C15 : 0 and anteiso-C17 : 0. The polar lipid profile of strain CCMF41T contained major amounts of diphosphatidylglycerol followed by an unidentified glycolipid, phosphatidylglycerol and an unknown phospholipid. Based on its phylogenetic,phenotypic and chemotaxonomic distinctiveness, strain CC-MF41T represents a novel species of Leucobacter, for which the name Leucobacter zeae sp. nov. is proposed. The type strain isCC-MF41T (=BCRC 80515T=LMG 27265T).
Asunto(s)
Actinomycetales/clasificación , Filogenia , Rizosfera , Microbiología del Suelo , Zea mays/microbiología , Actinomycetales/genética , Actinomycetales/aislamiento & purificación , Aminobutiratos/química , Técnicas de Tipificación Bacteriana , Composición de Base , Pared Celular/química , ADN Bacteriano/genética , Ácidos Grasos/química , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico , Fosfolípidos/química , Pigmentación , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Taiwán , Vitamina K 2/químicaRESUMEN
This study was undertaken to assess genetic diversity among Gordonia species present in heavily oil-contaminated sites using both a culture-dependent and a culture-independent (PCR-denaturing gradient gel electrophoresis (DGGE)) approach. Soil samples for this purpose were collected from 8 different heavily (crude) oil-contaminated industrial park sites located around Kaohsiung County, Taiwan. Using Gordonia-specific PCR-DGGE, a significant increase in Gordonia species diversity was noted in 1% heavily oil-enriched soil. A total of 67 strains were scored and identified as Gordonia after genus-specific PCR amplification and sequencing. BOX-PCR fingerprinting of culturable Gordonia showed wide strain diversity. A total of 33 different strains were identified from most of the sampling sites. Based on gyrB gene sequence analysis, all Gordonia strains could be segregated into five major clusters. Gordonia amicalis was the predominant species in all oil-amended soil samples. Isolates sharing <98.5% gyrB gene sequence similarities with Gordonia type strains represent indigenous novel Gordonia species. Variations in phenotypic characteristics further confirm the presence of a wide range of species and strain diversity among Gordonia isolates. Based on the genotypic and phenotypic details obtained here, we conclude that heavily oil-contaminated soil supports diverse indigenous Gordonia strains.
Asunto(s)
Bacteria Gordonia/genética , Bacteria Gordonia/aislamiento & purificación , Petróleo/metabolismo , Filogenia , Microbiología del Suelo , Contaminantes del Suelo/metabolismo , Proteínas Bacterianas/genética , Técnicas de Tipificación Bacteriana , Girasa de ADN/genética , Variación Genética , Bacteria Gordonia/clasificación , Bacteria Gordonia/metabolismo , Datos de Secuencia Molecular , TaiwánRESUMEN
A nested-PCR amplification combined with denaturing gradient gel electrophoresis (PCR-DGGE) approach was used to detect and identify Gordonia populations from wastewater treatment plant foam samples. The PCR-amplified region (position 722-1119) by specifically designed primers G699F and G1096R covered the hypervariable region of the Gordonia 16S rRNA gene sequence. This approach successfully distinguished Gordonia species to the interspecies level. The differential ability of PCR-DGGE analysis was effectively used to separate 12 Gordonia species belonging to different 16S rRNA gene-based phylogenetic lineages into 8 groups. Based on this method, the minimum limit of Gordonia detection was 5 x 10(4) CFU.g -1 in the seeded soil samples. The PCR-DGGE bands obtained were excised and identified by sequence analysis. Gordonia polyisoprenivorans, Gordonia amicalis, DGGE type II Gordonia species, and an uncertain Gordonia species dominated the activated sludge foam samples. Results of this study indicate that the detection and analyses of genus Gordonia within a complex microbial community could be accomplished using the PCR-DGGE approach to a larger extent, with certain limitations. Detection of diverse Gordonia populations in foam samples from wastewater treatment plants revealed the significant role of Gordonia in biological foaming during wastewater treatment. The nested-PCR amplification and DGGE can be used as a diagnostic tool for the early detection of foaming incidents in wastewater treatment plants using Gordonia as indicator organism.