A Gram-negative, motile, non-spore-forming and moderately halophilic ellipsoid-shaped marine coccobacillus, designated strain SS011B1-4T, was isolated from benthic sediment of the South China Sea. Optimum growth occurred at 30-37 6C, pH 7.5-8.0 and 4-8% (w/v) NaCl. Strain SS011B1-4T utilized a variety of organic substrates as sole carbon sources, but did not utilize toluene, n-tetradecane or crude oil. Strain SS011B1-4T had ubiquinone-9 as the major respiratory quinone and C18: 1v9c, C16: 0 and C12: 0.3-OH as the predominant fatty acids. The genomic DNA G+C content was 62.2 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain SS011B1-4T belonged to the genus Marinobacter of the Gammaproteobacteria. The results of the phenotypic, phylogenetic and genomic analyses revealed that strain SS011B1-4T represents a novel species of the genus Marinobacter. The name Marinobacter segnicrescens sp. nov. is therefore proposed, with strain SS011B1-4T (5LMG 23928T5CGMCC 1.6489T) as the type strain.

A Gram-negative, non-motile, rod-shaped bacterium, strain SS011B1-20T, was isolated from sediments of the South China Sea. Growth occurred at NaCl concentrations between 0 and 10% and at temperatures between 10 and 37 6C. Strain SS011B1-20T contained Q-10 as the major respiratory quinone and C18: 1v7c (81.2%), C16: 0 (7.0%) and C18: 1 methyl (4.3%) as the predominant fatty acids. The G+C content of the genomic DNA was 64.7 mol%. A phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain SS011B1-20T belonged to a clade within the genus Oceanicola in the Alphaproteobacteria, the highest sequence similarities being found with respect to Oceanicola batsensis (96.3%) and with Oceanicola granulosus (94.9%). Strain SS011B1-20T could be clearly distinguished from other Oceanicola species on the basis of the genotypic, phenotypic and phylogenetic data. Thus, it is proposed that strain SS011B1-20T represents a novel species of the genus Oceanicola, with the name Oceanicola nanhaiensis sp. nov. The type strain is SS011B1-20T (=LMG 23508T=CGMCC 1.6293T).

目前自然界中只有极少部分微生物能够得到培养，严重阻碍了对微生物生命活动规律的研究和微生物资源的开发。改进传统培养方法，采用新型培养技术，提高微生物可培养性，大量培养自然界中存在的微生物，从而更全面、准确地了解微生物细胞的生命规律、获悉微生物群落中各种微生物之间的动态相互作用和相互协调的规律，对环境微生物工艺进行准确地设计、精细地调控和高效地利用。简要介绍了微生物不可培养的原因，系统总结了有关提高微生物可培养性方法的最新研究进展，提出研究中存在的问题，并阐述了模拟自然环境条件、强调微生物相互关系是提高微生物可培养性的关键。

根据油田外排水中常见铁细菌的16SrRNA特异性保守序列，设计和合成了4种荧光探针，利用荧光原位杂交方法，分别利用它们对胜利油田孤岛采油厂、胜利采油厂1号和2号综合处理站外排水中存在的铁细菌的种类和数量进行检测，分析了各外排水中铁细菌的群落结构.结果表明，利用基因探针能快速对胜利油田外排水中的铁细菌进行检测:在孤岛采油厂、胜利采油厂1号和2号综合处理站的外排水中，利用4种探针的组合探针检测到的铁细菌细胞数量分别占样品中微生物总细胞数量的11.0%、12.8%和9.0%, 其中Leptothrix和Sphaerotilus，以及Leptospirillum fer-riphilum 为胜利油田外排水中的3种优势铁细菌，分别占水样中总微生物细胞数的2.94%±0.52%～3.39%±0.52%和2.24%±0.16%～2.63%±0.49%；而Leptospirillum ferrooxidans和Acidithiobacillus spp.的种群则较小.3个污水处理站中铁细菌群落结构差异较大，而多样性相差不大.利用4种探针的各种组合对外排水中铁细菌的检测表明，单探针能够很好地分析外排水中铁细菌的群落结构，而组合探针能快速、较准确地检测外排水中铁细菌的数量，比传统的绝迹稀释法具有快速、准确、直观等优点。