粪产碱杆菌和木糖氧化杆菌败血症：附8例临床分析

本文通过对粪产碱杆菌和木糖氧化杆菌败血症的临床分析，结果表明条件致病菌致病日益增多，并引起严重败血症，这类败血症酷似伤寒的临床表现，易误诊，而且这类菌株对常用抗生素具有耐药性，合理使用抗生素，维持正常微生态平衡是临床工作者的重要课题。     

水稻根际联合固氮细菌的研究

从我国南方水稻根部分离到3株氧化型革兰氏阴性细菌,编号为A1601,A1701和A1702。经15N示踪实验证明,它们均有较高的固氮能力。在无氮培养基中加入少量稻根浸出液进行培养后,可使固氮酶活性明显提高。根据菌株的形态和生理生化等特征鉴定,3株菌均为产孽菌属的细菌,分别为争论产碱菌(Alcaligenes paradoxus A1601),反硝化产碱蔺木糖氧化亚种(Alcaligenes denitrificans subsp.xylosoxydons A1701)和反硝化产碱菌反硝化亚种(Alcaligenes denitridicans subsp.denitrificans A1702)。这是继粪产碱菌(Alcaligenesfaecalis)之后,发现的产碱菌属中另外3株未见报道的固氮细菌。     

长白山温泉无氧芽孢杆菌的分离鉴定

[目的]对长白山温泉中嗜热微生物进行分离鉴定,并了解其生理生化特性.[方法]采用橄榄油富集培养基,稀释平板涂布法对长白山温泉样品进行分离得到一株嗜热菌CBS-5;在电子和光学显微镜下观察菌体形态和芽孢;应用生理生化试验、16S rDNA序列分析以及(G C)mol%含量等方法对菌株特性进行鉴定.[结果]菌株CBS-5为革兰氏阳性菌,无鞭毛,产端生芽孢,最适生长温度为65℃,最适pH7.7左右,能以蔗糖、麦芽糖和乳糖等作为唯一碳源生长,具有酯酶和过氧化氢酶活性,对卡那霉素、红霉素和硫酸新霉素等抗生素均无抗性.Tm法测定该菌的(G C)mol%含量为41.9%.脂肪酸成分分析表明在CBS-5中iso-15:0的含量最高,为24.20%,与无氧芽孢杆菌属成员一致.以该菌的16S rDNA序列为基础构建了系统发育树;16S rDNA序列同源性比对表明该菌与无氧芽孢杆菌属各种之间的同源性在95.1%-98.5%之间.[结论]菌株CBS-5(=JCM 15484)是一株嗜热无氧芽孢杆菌,具有产酶活性,对于研究和开发化工、食品和环境保护方面的工业用酶具有重要价值.     

发酵乳中动物双歧杆菌乳亚种分离及鉴定

采用改良MRS培养基从蒙牛冠益乳酸奶中选择性分离得到2种乳酸菌, 表型特征检测初步确定目标菌株BB-12, 该菌株符合双歧杆菌属特征描述。通过Biolog微生物自动鉴定系统鉴定、16S rDNA序列分析、atpD基因序列分析, 多相鉴定表明: 菌株BB-12为动物双歧杆菌乳亚种(Bifidobacterium animalis subsp. lactis)。系统发育学分析表明: atpD基因序列比16S rDNA序列在动物双歧杆菌亚种水平鉴定上有更好的分辨率。     

一株油藏嗜热厌氧杆菌的分离、鉴定及代谢产物特征

[目的]了解油藏环境中细菌的生理生化特性及代谢产物.[方法]采用Hungate厌氧操作技术从胜利油田罗801区块油层采出水中分离到一株厌氧杆菌SC-2.采用生理生化鉴定结合16S rDNA序列的系统发育学分析确定该菌株的系统发育地位,用气相色谱分析其代谢产物.[结果]菌株SC-2为严格厌氧的革兰氏阴性杆菌,菌体大小为0.38 um×1.7um-3.9um,单生、成对或成串生长,产端生芽孢.温度生长范围40℃-75℃(最适温度70℃);pH范围5.5-9.5(最适pH 6.5);NaCl浓度范围0%～5%(最适NaCl浓度0%).能够利用葡萄糖、麦芽糖、甘露糖、木糖等多种碳水化合物,发酵葡萄糖的产物是乙醇、乙酸、丙酸、H2、CO2及少量的乳酸.菌株SC-2的(G C)mol%含量为30.8%,与Thermoanaerobacter mathranii subsp.mathranii的16S rDNA序列相似性为99.85%.菌株利用葡萄糖产乙酸、乙醇的最佳初始pH为8.0;酵母粉能刺激生长并显著提高发酵葡萄糖的产酸、产醇率;培养基中添加4%(V/V)的乙醇能明显抑制菌体生长.[结论]菌株SC-2是从特殊生境(油层采出水)中分离到的一株嗜热、耐盐的厌氧菌,其发酵葡萄糖产生的代谢产物有利于改善油藏中的微环境.菌株SC-2与T.mathranii subsp.mathranii 11426T的最适pH和最大耐受NaCl浓度有所不同,且二者的(G C)mol%含量差异较大.     

药用植物内生芽孢杆菌的多样性和系统发育研究

[目的]了解药用植物内生芽孢杆菌的生物多样性.[方法]采用数值分类、16S rDNA PCR RFLP、BOX-PCR指纹图谱和16S rDNA序列分析技术对分离于几种药用植物的内生芽孢杆菌和已知参比菌株进行表型、遗传多样性及系统发育研究.[结果]供试菌株在数值分类聚类分析中在84%的相似水平上产生13个表观群.16S rDNAPCR-RFLP分析表明供试菌株表现出丰富的遗传多样性.BOX-PCR指纹图谱分析进一步证明药用植物的内生芽孢杆菌的基因组也具有多样性,聚群的结果与数值分类有较好一致性.用软件在Genbank中进行所得序列的同源性检索,并构建系统发育树.由16S rDNA序列分析可知,供试的代表菌株SCAU11与球形芽孢杆菌(Bacillus sphaericus)亲缘关系最近,SCAU78和SCAU25为枯草芽孢杆菌(Bacillus subtilis)的两个亚种,代表菌株SCAU39与巨大芽孢杆菌(Bacillus megaterium)的亲缘关系最近.[结论]研究结果表明药用植物内生芽孢杆菌具有明显的表型和遗传多样性.     

一种耐铀植物促生菌的筛选及促生特性研究

采用富集培养法和LB平板法从铀尾矿污染区蓼科植物酸模根部中筛选和分离一株具有较强铀耐受能力的细菌菌株,通过特征反应和平均吸光度法分析其生长特性和不同培养条件下植物促生特性。结果表明:该菌株可在铀浓度350 mg/kg(土)条件下生长。具有较强的分泌IAA能力,普通条件下24 h产IAA 40.21 mg/L,最佳产IAA条件为温度为35℃,pH 7,转速为150 r/min,氮源为酵母膏,碳源为甘油;兼具ACC脱氨能力,普通条件下24 h产ACC酶活为0.32 U/μg,最佳的ACC酶活条件为温度为30℃,pH 7,转速180 r/min。结合形态学特征,生理生化初步特征和16s rDNA序列确定菌株为木糖氧化无色杆菌。不同铀浓度的盆栽实验接种该菌种能使苜蓿干重分别提高17.9%-110.4%;对铀的富集率分别提高12.2%-180.6%。     

食品抗氧剂-D-异抗坏血酸的研究——Ⅰ.2-酮基-D-葡萄糖酸产生菌的筛

从199株细菌中筛选出产2-酮基-D-葡萄糖酸的高产菌株2株。产物对葡萄糖的克分子转化率达85.93%、87.56%以上。经生物学鉴定,菌株E301为恶臭假单胞菌(Pseudomonas putida),菌株E54为产碱菌属的一个新种,为产酮产碱菌(Alcaligenes ketogenes nov.sp.)。将发酵产物及其转化成的D-异抗坏血酸钠样品经红外吸收光谱比较,结果均与标准品相同。可确定这两株菌的发酵产物确系2-酮基-D-葡萄糖酸钙。     

一株毒死蜱降解细菌的分离鉴定及其在土壤修复中的应用

从蔬菜大棚土壤中分离到一株能以毒死蜱为唯一碳源和能源生长的菌株DSP3,该菌在含毒死蜱（100mg/L）的酵母膏和蛋白胨与同样毒死蜱含量而无酵母膏蛋白胨的无机盐培养基中,18d对毒死蜱的降解率分别为986%和762%;在土壤实验中20d对毒死蜱（100mg/kg）的降解率接近100%,加入DSP3菌在蔬菜大棚新鲜土壤中能有效促进毒死蜱在土壤中的降解。根据生理生化特征、16S rDNA序列分析、（G+C）mol%测定和DNA同源性分析,将菌株DSP3鉴定为粪产碱杆菌（Alcaligenes faecalis）。     

一株Ⅱ型甲烷氧化菌中甲烷单加氧酶基因和16S rDNA的分析

[目的]利用分子生物学方法对-株甲烷氧化菌Methylosinus trichosporium IMV 3011中的16S rDNA和溶解性甲烷单加氧酶基因序列进行分析并探索其进化分类地位.[方法]利用基因数据库已有的基因序列信息,设计PCR扩增引物和基因测序引物,对溶解性甲烷单加氧酶基因和16s rDNA进行扩增和测序,并进行溶解性甲烷单加氧酶的6个基因和氨基酸序列与同类菌株的相应序列进行联配分析.[结果]获得了全长为5319 bp甲烷单加氧酶基因序列和长度为1290 bp的16S rDNA序列.该菌株与Methylosinus trichosporium OB3b中相对应基因的同一性是99.0%～82.7%,MMOX氨基酸序列的同一性为99.4%～81.8%,相似性为99.8%～89.2%.基于以上分析表明MMOX组分有很高的序列保守性,特别是在活性中心区域.[结论]菌株IMV3011属于甲基弯菌属,最近似的菌株是Methylosinus trichosporium OB3b.     

抗草甘膦酵母菌ZM-1的分离鉴定及其生长降解特性

以福州市郊区的耕作土壤为研究材料, 利用草甘膦为选择压力, 通过富集、驯化培养, 分离出一株对草甘膦具有高耐受和降解作用的酵母菌菌株ZM-1, 结合生理生化特征及26S rDNA D1/D2区序列分析将其初步鉴定为胶红酵母菌(Rhodotorula mucilaginosa)。菌株ZM-1能以草甘膦为唯一碳、氮源生长, 对草甘膦的最高耐受浓度为50 g/L。在草甘膦初始浓度为1 g/L的无机盐培养基中, 30°C、150 r/min 摇床振荡培养7 d, 草甘膦降解率为85.38%。适合菌株ZM-1生长及降解草甘膦的最佳条件为: 草甘膦初始浓度1 g/L, 接种量4%, 温度30°C, pH 值5.5-6.0, 装料量50 mL/250 mL。菌株ZM-1是一株良好的草甘膦耐受菌, 可用于草甘膦污染环境的生物修复, 也可能成为转基因抗草甘膦作物的一个很好资源。     

细菌纤维素生产菌株的分离和菌种初步鉴定

从长膜的醋醅中分离出一株发酵生产细菌纤维素产量较高且稳定的醋酸菌M12。根据《常见细菌系统鉴定手册》和《伯杰氏细菌鉴定手册》第九版,对醋酸菌M12进行了形态和生理生化特征的分析、测定了G＋Cmol％含量,初步鉴定该菌为醋化醋杆菌木质亚种（Acetobacter xylinum subsp.xylinum,又称木醋杆菌）。     

The tyrosine decarboxylation test does not differentiate Enterococcus faecalis from Enterococcus faecium

According to the current edition of the Bergey's Manual of Systematic Bacteriology [11] the tyrosine decarboxylation test allows the differentiation of enterococci. Tyrosine is decarboxylated to the biogenic amine tyramine by E. faecalis and not by E. faecium strains. In the present study we sequenced the16S rDNA of two tyramine-producing strains, BIFI-56 and BIFI-58, presumptively classified as E. faecalis. Their 16S rDNA were identical to the same fragment from the E. faecium type strain. Several E. faecium strains were then checked for their ability to decarboxylate tyrosine and also a putative tyrosine decarboxylase-coding gene was PCR amplified from these strains. All the strains confirmed as E. faecium produced tyramine and possessed a DNA fragment coding for a putative tyrosine decarboxylase. The concordance of the two methods allows us to conclude that the tyrosine decarboxylase test cannot be used in the differentiation of E. faecalis from E. faecium since at least some E. faecium strains are tyramine producers.     

Alcaligenes faecalis subsp. parafaecalis subsp. nov., a bacterium accumulating poly-beta-hydroxybutyrate from acetone-butanol bioprocess residues

The authors have previously isolated a solvent tolerant bacterium, strain G(T), (T = type strain) capable to convert acetone-butanol bioprocess residues into poly-beta-hydroxybutyrate. Strain G(T) was initially identified as Alcaligenes spp by standard bacteriological tests. In this study the taxonomic position of the bacterium was investigated in detail. The 165 rDNA sequence analysis, the G + C content of DNA (56 mol%) and the presence of ubiquinone Q-8 confirmed strain G(T) as a representative of the genus Alcaligenes. In the polyamine pattern of the bacterium putrescine and cadaverine were detected, but only trace amounts of 2-hydroxyputrescine. The extremely low content of 2-hydroxyputrescine is remarkable, since this unique diamine is a common marker for beta-proteobacteria. Phylogenetic analyses of 16S rDNA demonstrated that Alcaligenes sp. G(T) is most closely related to the species Alcaligenes faecalis (99.6% sequence similarity to A. faecalis HR4 and 98.7% sequence similarity to A. faecalis [ATCC 8750T = DSM 30030T]. On the basis of DNA-DNA relatedness (56% similarity), the unique polyamine pattern, the physiological and biochemical differences strain G(T) could be distinguished from the species A. faecalis. Therefore, a new subspecies for the species Alcaligenes faecalis is proposed; Alcaligenes faecalis subsp. parafaecalis subsp. nov.     

荚膜红细菌的分离鉴定及其协同固氮作用

从上海南汇县的水稻根系中分离得到一株光合固氮菌ＳＤＨ２,经形态、细胞膜结构、生理生化等特征的分析鉴定,以伯杰细菌鉴定手册第九版和ＪＦＩｍｈｏｆｆ的光合硫细菌和绿硫细菌的生理学和分类^［１］一文为依据,确定该菌为荚膜红细菌Ｒｈｏｄｏｂａｃｔｅｒｃａｐｓｕｌａｔｕｓ。同时,发现该菌与水稻根表的其它固氮菌之间具有协同生长和协同固氮效应。     

苯酚高效降解菌的筛选和降解特性的研究

从天津市煤气厂的活性污泥中筛选、分离得到一株高效苯酚降解菌。经BIOLOG细菌自动鉴定系统及16SrDNA鉴定,该菌株为粪产碱杆菌(Alcaligenesfaecalis)。苯酚降解实验证实,该菌能在76h内完全降解1600mg·L-1的苯酚,并且随着苯酚浓度的增加,底物抑制作用增强,细胞得率下降。     

Characterization and phylogenetic analysis of an entomopathogenic Bacillus cereus strain WGPSB-2 (MTCC 7182) isolated from white grub, Anomala dimidiata (Coleoptera: Scarabaeidae)

White grubs (Coleoptera: Scarabaeidae) are cosmopolitan and polyphagous insect pests of agricultural crops, forests and pastures around the world. The lack of an environmentally sound approach for white grub management has prompted the exploration and detection of a novel microbial biocontrol agent against these sub-terranean insect pests. In this study we describe the isolation, establishment of pathogenesis, biochemical characterization and phylogenetic analysis of an entomopathogenic Bacillus cereus strain WGPSB-2 (MTCC 7182), isolated from an atrophied pupa of Anomala dimidiata, collected from the N.W. Indian Himalayas. The sequencing and subsequent comparison of the 16S rDNA revealed that the strain has100% similarity with Bacillus cereus sequences. Phylogenetic analysis of the 16S rDNA sequence revealed that the isolate is closely related to Bacillus thuringiensis and Bacillus sphaericus. In vitro bioassays showed that the isolate was able to infect and cause 92 and 67% mortality in second instar larvae of Anomala dimidiata and Holotrichia seticollis, respectively. The infected larvae exhibited bacterial septicemia like symptoms and mortality occurred between the third and ninth weeks after inoculation. The culture has been granted the accession number MTCC 7182 by the Microbial Type Culture Collection and Gene Bank, Institute of Microbial Technology, Chandigarh, India.     

Isolation and Characterization of a Pseudomonas Oleovorans Degrading the Chloroacetamide Herbicide Acetochlor

To date, no pure bacterial cultures that could degrade acetochlor have been described. In this study, one strain of microorganism capable of degrading acetochlor, designated as LCa2, was isolated from acetochlor-contaminated soil. The strain LCa2 is Pseudomonas oleovorans according to the criteria of Bergey’s manual of determinative bacteriology and sequence analysis of the partial 16S rRNA gene. Optimum growth temperature and pH were 35 °C and 8.0, respectively. The strain could degrade 98.03% of acetochlor treated at a concentration of 7.6 mg l⁻¹ after 7 days of incubation and could tolerate 200 mg l⁻¹ of acetochlor. When the acetochlor concentration became higher, the degradation cycle became longer. The acetochlor biodegradation products were identified by GC–MS based on mass spectral data and fragmentation patterns. The main plausible degradative pathways involved dechlorination, hydroxylation, N-dealkylation, C-dealkylation and dehydrogenation.     

高效絮凝剂产生菌的筛选及絮凝活性研究

从污泥中分离筛选出1株具有高絮凝活性的细菌菌株F78,对其进行了分子鉴定,测得该菌16SrDNA长度为1501 bp,在GenBank中的登录号为EU443097,序列比对结果显示,该菌与粪产碱杆菌(Alcaligenes faecalis)的16S rDNA碱基序列相似性为99%。絮凝活性物质可由F78菌株分泌到胞外,通过对絮凝活性影响因素的研究,发现Ca2 的助凝效果比Fe3 、Fe2 、K 、Na 好;在高岭土悬液pH 3.0~12.0范围内,能保持较高的絮凝活性;菌株F78产生的絮凝活性物质具有良好的热稳定性。     

Identification of xenobiotic-degrading isolates from the beta subclass of the Proteobacteria by a polyphasic approach including 16S rRNA partial sequencing.

Nineteen gram-negative, aerobic, biodegradative isolates were identified by using a polyphasic taxonomic approach. The presence of the specific polyamine 2-hydroxyputrescine and the presence of a ubiquinone with eight isoprenoid units in the side chain (ubiquinone Q-8) allowed allocation of these organisms to the beta subclass of the Proteobacteria. On the basis of the results of additional characterization experiments (i.e., API 20NE tests, determinations of soluble protein patterns, and DNA-DNA hybridization experiments), we classified six isolates as either Comamonas testosteroni, Comamonas acidovorans, or Alcaligenes xylosoxidans subsp. denitrificans. By using the same criteria we allocated two additional isolates to the genus Alcaligenes. A comparison of a 16S rRNA fragment (positions 1220 to 1377; Escherichia coli nomenclature) indicated that the remaining isolates should be allocated as follows: one is a member of C. testosteroni and one is a member of Acidovorax facilis, as confirmed by the results of additional DNA-DNA hybridizations; two others probably belong to the family Alcaligenaceae; six are related to "Alcaligenes eutrophus"; and one, strain NRRL 12228, occupies an isolated position.