一株甲基对硫磷降解菌——米曲霉JMUPMD-2的分离与鉴定

对一株新分离的、能以甲基对硫磷为唯一磷源生长的菌株——JMUPMD-2利用形态观察和rDNA ITS序列分析对JMUPMD-2进行鉴定; 用气相色谱法检测培养过程中甲基对硫磷浓度的变化, 确定甲基对硫磷降解速率。该菌株的rDNA ITS序列与米曲霉 (Aspergillus oryzae)的同源性为99%, 菌落形态和显微形态都与米曲霉特征相符, 因此鉴定为米曲霉; 以350 μg/L甲基对硫磷为唯一磷源和350 μg/L甲基对硫磷及1 g/L K2HPO4组成的混合磷源分别培养该菌株, 200 h后的分解量分别为189 μg/L及28 μg/L。该菌株的胞内提取液具有明显的甲基对硫磷降解酶活性。     

一株高效利用木糖的酵母菌的分离及鉴定

从256个自然试样中筛选到1株高效转化D-木糖为木糖醇的酵母菌株441-28—1。初始木糖质量浓度为90g/L的条件下,24h内的木糖利用效率为3．0g／（L·h）。通过高效液相分析,菌株441-28—1的主要代谢产物为木糖醇。在初始木糖质量浓度为65g/L的条件下,摇瓶分批发酵,木糖醇生成速率达1．1g／（L·h）,木糖醇转化率为70％。经过形态、生理生化特征测定,以及ITS序列分析（GenBank的登记号为EU121523）,将441-28—1菌株鉴定为热带假丝酵母（Candida tropicalis）。Candida tropicalis（热带假丝酵母）已保存于中国高校工业微生物资源数据平台,保藏编号CICIM Y0092。     

假丝酵母属疑难菌株大亚基rDNA D1/D2区域序列分析及其分类学意义*

对根据常规形态和生理生化性状难以确定分类学地位的8株假丝酵母菌,进行了以大亚基(26S) rDNA中D1/D2区域(约500~600 bp)的碱基序列分析为依据的分子分类学研究。根据系统树上所显示的供试菌株与假丝酵母属及相关子囊菌酵母已知种的亲缘关系,以及与最近缘种模式菌株D1/D2区域序列的相似性比较,确定了各个菌株的归属。本研究也显示了DNA序列分析在假丝酵母菌快速鉴定中的优越性。     

假丝酵母属疑难菌株大亚基rDNA D1/D2区域序列分析及其分类学意义

对根据常规形态和生理生化性状难以确定分类学地位的8株假丝酵母菌,进行了以大亚基(26S) rDNA中D1/D2区域(约500～600 bp)的碱基序列分析为依据的分子分类学研究.根据系统树上所显示的供试菌株与假丝酵母属及相关子囊菌酵母已知种的亲缘关系,以及与最近缘种模式菌株D1/D2区域序列的相似性比较,确定了各个菌株的归属.本研究也显示了DNA序列分析在假丝酵母菌快速鉴定中的优越性.     

假丝酵母属疑难菌株大亚基rDNAD1／D2区域序列分析及其分类学意义

对根据常规形态和生理生化性状难以确定分类学地位的8株假丝酵母菌,进行了以大亚基（26S）rDNA中D1/D2区域（均500-600bp)的碱基序列分析为依据的分子分类学研究。根据系统树上所显示的供试菌株与假丝酵母属及相关子囊菌酵母已知种的亲缘关系,以及与最近缘种模式菌株D1/D2区域序列的相似性比较,确定了各个菌株的归属,本研究也显示了DNA序列分析在假丝酵母菌快速鉴定中的优越性。     

一株对硝基苯胺降解菌Microbacterium sp. PNA8的分离鉴定及其降解条件研究

从污泥中分离得到一株能以对硝基苯胺为唯一碳源、氮源和能源生长的细菌菌株PNA8。经过对其形态特征、生理生化特性、以及16S rRNA序列分析, 该菌株初步鉴定为Microbacterium sp.。进一步研究表明, 菌株PNA8利用对硝基苯胺生长和降解的最适温度和pH分别是30°C和7.0。培养基中添加定量酵母膏有利于菌株的生长及其对对硝基苯胺的降解。最适条件下, 在培养液中添加0.4 g/L酵母膏, 4 d内0.3 mmol/L对硝基苯胺降解率可达100%。     

无机磷分解菌BL-11的鉴定及其解磷能力研究

研究了解磷菌株BL-11的菌体形态、生理生化特性,结合该菌的16SrDNA序列分析结果,将菌株BL-11鉴定为侧孢短芽孢杆菌。菌株BL-11在以Ca3(PO4)2为唯一磷源的培养液中的可溶性磷得率为10.91%;在以砂子为唯一磷源的培养液中,可溶性磷得率为1.56%。分解Ca3(PO4)2的最佳条件为30℃,180r/min,pH7-8;最佳培养基配方为蔗糖20g/L,(NH4)2HCO30.3g/L,MgSO4.7H2O0.5g/L,NaCl0.3g/L,KCl0.5g/L,FeSO40.03g/L,MnSO4.H2O0.03g/L。     

类胡萝卜素产生菌种的鉴定

于福建红酒酒糟中分离、筛选得到1株编号为B-5的产色素菌株。对该菌株所产色素进行定性分析,结果表明该色素为类胡萝卜素;对菌株进行常规形态和生理生化特性分析,结果表明该菌株为单细胞,呈卵圆形,芽殖;在固体培养基上,菌落呈深红色,菌落表面湿润、粘稠,边缘整齐,易被挑起;在液体培养基中,产生沉淀。无子囊孢子;无假菌丝形成。葡萄糖发酵试验为阴性,硝酸钾试验为阳性,耐高渗试验为阴性,产类淀粉化合物为阴性,37℃生长为阳性。利用26S rDNA D1/D2区域序列分析法对该菌株进行序列比对鉴定,结果表明,该酵母菌的序列与粘性红圆酵母（Rhodotorula mucilaginosa）模式菌株的序列同源性100%,结合该菌株常规形态和生理生化特性,鉴定该菌株为粘性红圆酵母（Rhodotorula mucilaginosa）。     

低温氨氮降解菌的筛选及降解能力研究

目的:筛选低温高效氨氮降解菌株,探讨其脱氮能力。方法:采用富集培养和纳氏试剂平板显色法分离筛选低温高效氨氮降解菌株;通过形态与生理生化特性、16S rDNA序列分析以及BIOFOSUN微生物鉴定分析系统鉴定菌株,采用液体培养研究菌株的氨氮降解能力和反硝化能力。结果:获得1株低温高效氨氮降解菌株WSW-1001,经形态、生理生化特性、16S rDNA序列以及BIOFOSUN微生物鉴定分析系统鉴定为荧光假单胞杆菌(Pseudomonas fluorescens)。该菌株具有较强硝化和反硝化能力,初始氨氮浓度为5 mg/L,8℃培养24 h,氨氮降解率71.7%,无亚硝酸盐积累。结论:菌株WSW-1001低温氨氮降解能力较强,具有潜在应用价值。     

一株苯酚降解菌的筛选、鉴定及其降解特性

本研究采用逐量分批驯化的方法,从造纸废水中分离得到一株能够以苯酚为唯一碳源生长的苯酚降解菌株F5-1.经形态观察、生理生化特性鉴定及16S rDNA序列分析,将该菌株鉴定为克雷伯菌(Klebsie-lla sp.).该菌株能够在7 h时完全降解初始浓度为100 mg/L的苯酚,降解苯酚主要发生在生长对数期;在pH 5.0～9.0,NaCl浓度0～80 g/L,温度20～40℃范围内,菌株F5-1均可有效降解初始浓度为100～1 200 mg/L的苯酚;能够耐受的最大苯酚浓度为1 500 mg/L.本研究结果表明,F5-1菌株对处理环境条件复杂的含酚废水具有潜在的应用前景.     

Degradation of malic acid by Issatchenkia orientalis KMBL 5774, an acidophilic yeast strain isolated from Korean grape wine pomace

Several yeast strains degrading malic acid as a sole carbon and energy source were isolated from Korean wine pomace after enrichment culture in the presence of malic acid. Among them, the strain designated as KMBL 5774 showed the highest malic acid degrading ability. It was identified as Issatchenkia orientalis based on its morphological and physiological characteristics as well as the nucleotide sequences of the internal transcribed spacer (ITS) I-5.8S rDNA-ITS II region. Phylogenetic analysis of the ITS I-5.8S rDNAITS II sequences showed that the KMBL 5774 is the closest to I. orientalis zhuan 192. Identity of the sequences of the KMBL 5774 was 99.5% with those of I. orientalis zhuan 192. The optimal pH of the media for the growth and malic acid degradation by the yeast was between 2.0 and 3.0, suggesting that the strain is an acidophile. Under the optimized conditions, the yeast could degrade 95.5% of the malic acid after 24 h of incubation at 30 degrees in YNB media containing 2% malic acid as a sole carbon and energy source.     

1株产纤维素酶木霉菌种的鉴定

对自行筛选分离的1株木霉菌进行形态学及分子生物学鉴定。采用CTAB法抽提其基因组总DNA,利用真菌通用引物ITS1和ITS4扩增菌株rDNA ITS区序列,扩增产物纯化后进行测序。测序结果在GenBank中进行同源性搜索,并下载部分具有代表性种的ITS序列,利用软件MEGA4构建分子系统发育树,通过序列分析,并结合形态学鉴定该菌属于半知菌亚门,丝孢纲,丛梗孢目,木霉属,康宁木霉(Trichoderma koningii)。     

Molecular divergence of the ssu rRNA gene and internal transcribed spacer 1 in Porphyra yezoensis (Rhodophyta)

Nucleotide sequences from the downstream of ssu rDNA to ITS1 region of the individual thalli of both wild-collected Porphyra yezoensis from three different sites and culture strains were determined to obtain the molecular features of strains in the P. yezoensis lineage. Wild-collected thalli identified by morphological systematics, included the individuals that were separate from the P. yezoensis lineage based on ssu rDNA and ITS1 sequence homologies and phylogenetic relationships constructed using ITS1 sequences. Ssu rDNA exon region nucleotide sequences were identical among the wild-collected and clture strains of P. yezoensis. However, all individual wild-collected P. yezoensis thalli had different ITS1 sequences, even among individuals from the same sites. Furthermore, two different ssu rDNA structures with and without an intron were found in individuals from the same site. These results indicated the possibility that the presence and sequence of introns and ITS1 sequences can be used as a characteristic to determine the origin of culture strains. Four of six culture strains examined had an identical sequence from the ssu rDNA to ITS1, while the sequences of another two strains differed. In this study, wild-collected and culture strain thalli sequences were not identical, although similar pairs were identified. This revised version was published online in July 2006 with corrections to the Cover Date.     

Genotyping of a miso and soy sauce fermentation yeast, Zygosaccharomyces rouxii, based on sequence analysis of the partial 26S ribosomal RNA gene and two internal transcribed spacers

We analyzed sequences of the D1D2 domain of the 26S ribosomal RNA gene (26S rDNA sequence), the internal transcribed spacer 1, the 5.8S ribosomal RNA gene, and the internal transcribed spacer 2 (the ITS sequence) from 46 strains of miso and soy sauce fermentation yeast, Zygosaccharomyces rouxii and a closely related species, Z. mellis, for typing. Based on the 26S rDNA sequence analysis, the Z. rouxii strains were of two types, and the extent of sequence divergence between them was 2.6%. Based on the ITS sequence analysis, they were divided into seven types (I-VII). Between the type strain (type I) and type VI, in particular, a 12% difference was detected. The occurrence of these nine genotypes with a divergence of more than 1% in these two sequences suggests that Z. rouxii is a species complex including novel species and hybrids. Z. mellis strains were of two types (type alpha and type beta) based on the ITS sequence. Z. rouxii could clearly be distinguished from Z. mellis by 26S rDNA and ITS sequence analyses, but not by the 16% NaCl tolerance, when used as the sole key characteristic for differentiation between the two species.     

高效氯氰菊酯降解菌CH7的分离鉴定及降解条件的优化

从农药厂活性污泥中,分离到一株能以高效氯氰菊酯为唯一碳源生长的细菌CH7。经生理生化试验和16S rD-NA分析,将菌株CH7鉴定为铜绿假单胞菌(Pseudomonas aeruginosa)。采用Box-behnken设计试验、响应面法(response surfacemethodology)优化菌株CH7的降解条件。在最优条件下(29.4°C,pH7.0,接种量0.15g/L),菌株CH7在12d内对100mg/L高效氯氰菊酯的降解率为90%。     

米尔顿姬小蜂rDNA ITS1和ITS2的序列分析及其分子鉴定

本研究测定了米尔顿姬小蜂Anselmella miltoni Girault的rDNA ITS1和ITS2序列,以探讨其分子鉴定方法。米尔顿姬小蜂的ITS1和ITS2侧翼区（18S和5.8S）序列相对稳定,ITS1和ITS2序列存在种间差异。根据18S rDNA部分序列,利用DNAMAN的Maximum Likelihood方法构建了与膜翅目其它科的系统发育树。根据米尔顿姬小蜂ITS1和ITS2序列设计了特异性引物,应用特异性引物对样品进行了PCR扩增,扩增效果理想,采用上述特异性引物可从单头米尔顿姬小蜂稳定地扩增出明显的目的DNA条带。因此,可以采用ITS1和ITS2区的特异性对米尔顿姬小蜂进行快速的分子鉴定。     

Phylogenetic position of the copepod-infesting parasite Syndinium turbo (Dinoflagellata, Syndinea)

Sequences were determined for the nuclear-encoded small subunit (SSU) rRNA and 5.8S rRNA genes as well as the internal transcribed spacers ITS1 and ITS2 of the parasitic dinoflagellate genus Syndinium from two different marine copepod hosts. Syndinium developed a multicellular plasmodium inside its host and at maturity free-swimming zoospores were released. Syndinium plasmodia in the copepod Paracalanus parvus produced zoospores of three different morphological types. However, full SSU rDNA sequences for the three morphotypes were 100% identical and also their ITS1-ITS2 sequences were identical except for four base pairs. It was concluded that the three morphotypes belong to a single species that was identified as Syndinium turbo, the type species of the dinoflagellate subdivision Syndinea. The SSU rDNA sequence of another Syndinium species infecting Corycaeus sp. was similar to Syndinium turbo except for three base pairs and the ITS1-ITS2 sequences of the two species differed at 34-35 positions. Phylogenetic analyses placed Syndinium as a sister taxon to the blue crab parasite Hematodinium sp. and both parasites were affiliated with the so-called marine alveolate Group II. This corroborates the hypothesis that marine alveolate Group II is Syndinea.     

基于ITS条形码序列的刺桐姬小蜂分子鉴定

【目的】刺桐姬小蜂Quadrastichus erythrinae Kim体型小,传统的形态学鉴定方法难以快速准确识别。【方法】本研究测定了刺桐姬小蜂的rDNA ITS1和ITS2序列,根据18S rDNA部分序列,利用MEGA的最大相似法(Maximum Likehood)构建系统发育树。根据刺桐姬小蜂ITS1和ITS2序列设计了特异引物,应用特异引物对单只刺桐姬小蜂进行PCR扩增,可稳定地扩增出明显的目的DNA条带。【结果】研究表明,基于ITS基因的DNA条形码技术可以用于刺桐姬小蜂的快速准确鉴定。【结论】因此,采用ITS1和ITS2区的特异性引物可对刺桐姬小蜂进行快速分子鉴定。     

Cloning of mpd gene from a chlorpyrifos-degrading bacterium and use of this strain in bioremediation of contaminated soil

An effective chlorpyrifos-degrading bacterium (named strain YC-1) was isolated from the sludge of the wastewater treating system of an organophosphorus pesticides manufacturer. Based on the results of phenotypic features, phylogenetic similarity of 16S rRNA gene sequences and BIOLOG test, strain YC-1 was identified as the genus Stenotrophomonas. The isolate utilized chlorpyrifos as the sole source of carbon and phosphorus for its growth and hydrolyzed chlorpyrifos to 3,5,6-trichloro-2-pyridinol. Parathion, methyl parathion, and fenitrothion also could be degraded by strain YC-1 when provided as the sole source of carbon and phosphorus. The gene encoding the organophosphorus hydrolase was cloned using a PCR cloning strategy based on the known methyl parathion degrading (mpd) gene of Plesiomonas sp. M6. Sequence blast result indicated this gene has 99% similar to mpd. The inoculation of strain YC-1 (10(6) cells g(-1)) to soil treated with 100 mg kg(-1) chlorpyrifos resulted in a higher degradation rate than in noninoculated soils. Theses results highlight the potential of this bacterium to be used in the cleanup of contaminated pesticide waste in the environment.