一株降解甾体雌激素的克雷伯氏菌ZY3

为研究甾体雌激素的生物降解,从某避孕药厂污水处理站的活性污泥中分离到1株降解甾体雌激素(3-甲氧基-17β羟基-1,3,5(10),8(9)-雌甾-4-烯,简称MHE)的高效菌ZY3,根据其菌体形态、生理生化特征,并结合16S rDNA序列分析,鉴定为克雷伯氏菌属．研究结果表明,菌株ZY3利用底物MHE的最适宜生长温度为25～37℃、pH为9．0～11．0．ρ(MHE)＞20 mg/L时,菌株生长受到抑制,72 h MHE最高降解率达81%．Na~+、Mg~(2+)和Ca~(2+)对菌株ZY3的生长有促进作用,而Sn~(2+)、Mn~(2+)、Cd~(2+)等重金属离子对ZY3菌株生长有较强的抑制作用．菌株ZY3对甾体化合物MHE和EE2有较强的利用能力,而以苯酚、蒽、萘等多环芳烃化合物作为唯一碳源时,菌株ZY3生长非常缓慢．     

Phenotypic and genetic characterization of a novel strain of Acidithiobacillus ferrooxidans （AF2）

A comparative study on the phenotypic and genetic characteristics among Acidithiobacillus ferrooxidans (AF2), a typic strain ATCC23270 and a previously isolated strain AF3 was performed. AF2 can use ferrous ion (Fe²⁺) or elemental sulfur (S⁰) as sole energy source, but oxidizes S⁰ more effectively than Fe²⁺, which is different from ATCC23270 and AF3. The G+C content of AF2 is 51.8% (molar fraction), however, ATCC23270 and AF3 strains have G+C content of 63.7% and 64.8% (molar fraction), respectively. The DNA-DNA hybridization results show that AF2 has 41.53% and 52.38% genome similarity to ATCC 23270 and AF3, respectively, but AF3 has a high genome similarity of 89.86% to ATCC 23270 strain. Rusticyanin (rus) and subunit III of aa₃-type cytochrome oxidase (coxC) genes are not detected in AF2, but Fe²⁺ oxidase (iro) gene can be detected. To understand the genomic organization of iro gene, a cosmid library of AF2 genome was constructed and iro gene-containing clone was screened. The sequencing result shows that although the nucleotide sequence of iro gene in AF2 is completely identical to that of ATCC 23270 strain, its genomic organization is different from that of ATCC 23270. In AF2, iro is located at downstream of purA gene, while it is located at downstream of petC-2 gene in ATCC 23270 strain. These results indicate that AF2 is a novel strain of A. ferrooxidans, and that phenotypic differences among the strains of A. ferrooxidans are closely correlated with their genetic polymorphisms.     

A novel salt-tolerant Micrococcus sp. DUT_AHX capable of degrading nitrobenzene

A novel strain of Micrococcus sp. DUT_AHX, which was isolated from the sludge of a nitrobenzene (NB)-manufacturing plant and could utilize NB as the sole carbon source, was identified on the basis of physiological and biochemical tests and 16S ribosomal DNA (rDNA) sequence analysis. It can grow at the temperature up to 40 °C or in the presence of NaCl concentration up to 12 g/L in Luria-Bertani (LB) medium. The optimal degradation conditions are as follows: temperature 37 °C, pH 7.0, and shaking speed 150 r/min. The strain involves a partial reductive pathway due to the release of ammonia and can also utilize 2-aminophenol as the sole carbon source. Furthermore, the enzyme activity tests show that crude extracts of NB-grown strain DUT_AHX mainly contain 2-aminophenol 1, 6-dioxygenase activity. The exploitation of salt-tolerant bacteria will be a remarkable improvement in NB bioremediation and wastewater treatment at high salinity and high temperature.     

Elizabethkingia sp. DBP-WUST对邻苯二甲酸二丁酯的降解特性研究

从武汉石化活性污泥中分离得到1株能高效降解邻苯二甲酸二丁酯（DBP）的菌株DBP-WUST.经形态学观察、生理生化特性试验及16SrDNA鉴定结果表明,该菌为Elizabethkingia sp..研究发现,该菌株较优的生长条件为：温度35℃,pH7,摇床转速150r/min,接种量7%.在较优生长条件下,菌株DBP-WUST能在60h将400mg/L的DBP全部降解.将菌株投加到实际炼油废水中,能有效降低废水的COD.     

嗜盐菌AB3中细菌视紫红质和系统发育研究

为了研究分析嗜盐古生菌物种与细菌视紫红质(BR)蛋白基因资源,分离纯化得到极端嗜盐古生菌AB3. 采用聚合酶链式反应(PCR)方法对其编码螺旋C至螺旋G的蛋白基因片断和16S rRNA基因进行了扩增,并测定了基因的核苷酸序列. 翻译出的氨基酸序列与已报道的相应片断进行对比,AB3中的螺旋C至螺旋G蛋白与其他菌株差异显著.基于BR蛋白和16S rDNA序列的同源性比较以及系统发育学研究表明,AB3是Natrinema属中的新成员. 菌株AB3的16S rDNA序列已被GenBank数据库收录,其序列号为AY277583.     

Microwave induced mutagenesis of Lactobacillus casei subsp. rhamnosus for enhancing L-lactic acid production

Mutagenesis of Lactobacillus casei subsp.rhamnosus X1-12 after low power microwave irradiation was investigated.Under a microwave power of 400 W and irradiation length of 3 min,a mutated strain W4-3-9 with high-yield L-lactic acid was obtained by screening.Compared with the starting strain X1-12,the L-lactic acid production of W4-3-9 was increased by 58.0% at a concentration of 115.8 g/L.The strain maintained the capability of producing a high L-lactic acid level after 10 generations.Cell surface morphology and DNA structures of parental and mutated strains were observed by atomic force microscopy (AFM).Amplified fragment length polymorphism (AFLP) analysis suggested the difference in AFLP band pattern between the mutated and non-mutated strains.Sequencing and BLAST analysis revealed that the catalytic site of lactate dehydrogenase (DHL) was changed due to the microwave induced mutation.     

一株来源于酒曲的纤溶酶产生茵的鉴定及其酶学性质

从酒曲中分离到一株纤溶酶产生菌,经形态及ITS序列分析鉴定为菊芋小孢根霉（Rhizopus microsporusvar．tuberosus）．酶学性质研究表明,该纤溶酶的最适作用温度为37℃,最适作用pH为7．0．在37℃保温4h酶活力仍保存95％,57℃下保温4h后仍有一定酶活．该酶具有广泛的酸碱适应性,在pH〈3．4时仍残留部分活性;最稳定的pH范围是6～8．Zn2＋、Cu2＋对酶活有抑制作用,Na2＋、Ca2＋、Mn2＋对酶活具有明显的促进作用．该酶在人工肠液中具有较好的稳定性,37℃保温4h后残余酶活仍然保持在80％以上,有望制成注射剂应用于临床。     

Aerobic biodegradation of diethyl phthalate by Acinetobacter sp. JDC-16 isolated from river sludge

A gram negative bacterium, named JDC-16, which can grow well on the substrate of phthalic acid esters (PAEs) as the sole source of carbon and energy, was isolated from river sludge. Based on the morphology, physiological and biochemical properties and analysis of 16S rRNA gene sequence, it was preliminarily identified belonging to the genus Acinetobacter. The result of substrates utilization range indicates that strain JDC-16 can utilize a variety of phthalates except for diisononyl phthalate (DINP). The degradation tests using diethyl phthalate (DEP) as the model compound show that the optimal pH and temperature for DEP degradation by Acinetobacter sp. JDC-16 is 8.0 and 35 °C, respectively. Meanwhile, degradation kinetics under various initial concentrations of DEP reveals that substrate depletion curves fit well with the modified Gompertz model with high correlation coefficient (R ²>0.99). Furthermore, the substrate induction test indicates that DEP-induction can apparently shorten the lag phase and enhance the degradation rate. This work highlights the potential of this isolate for bioremediation of phthalates-contaminated environments.     

不同条件下耐盐脱氮复合菌剂的脱氮特性

目的研究人工构建的高效耐盐脱氮复合菌剂在不同条件下的生长情况和脱氮效果,为优化培养条件、提高高盐废水的脱氮效率和处理实际废水提供运行参数．方法在转速125r／min的恒温振荡培养箱中,按6％接种复合菌剂,控制初始氨氮质量浓度100mg／L,进行36h静态脱氮试验．结果耐盐脱氮复合菌剂的脱氮最适m（C）：m（N）为15,最适氯化钠质量分数为3％,pH为7,温度为30℃．耐盐脱氮复合菌剂在氯化钠质量分数为3％～7％均能获得良好的生长和脱氮性能,脱氮率达到99．02％,反应末氨氮质量浓度低于1mg/L．结论耐盐脱氮复合菌剂具有一定耐盐性,脱氮过程中无硝态氮和亚硝态氮积累,可实现同步硝化反硝化,能提高高盐废水生物处理脱氮效率．     

喹啉降解菌的分离鉴定及在柴油脱氮中的应用

喹啉是一种有毒、难生物降解的有机氮化合物, 通过以喹啉为唯一氮源, 富集培养筛选出19 种能降解喹啉的菌株, 通过喹啉降解实验筛选出降解喹啉较好的HY9 菌株作为实验菌株, 喹啉降解曲线和细胞生长曲线测定表明, 菌株生长和喹啉的降解是同步的, 并且在50 ～ 70 h , 菌株的生长和降解达到最佳状态。研究了葡萄糖和初始喹啉体积对菌株降解喹啉的影响, 确定碳源是葡萄糖, 喹啉体积分数为1.4 mL/ L。正交实验确定了温度为35 ℃、pH 值为7.0、培养时间为4 d 和摇床转速为125 r/ min, 并且温度对细胞生长的影响最大, 其次是摇床转速、pH 值, 培养时间对其影响最小。柴油脱碱氮的初步实验表明, 脱除率为13 %, 比较低, 可能是油水混溶性不好所致, 设法提高油水混溶性是提高柴油碱氮脱除率的关键。     

双组分系统分析预测共生机制

为明确双组分系统在德氏乳杆菌保加利亚亚种和嗜热链球菌共生中起的作用,采用生物信息学手段,对二者的5个菌株的基因组进行扫描,对其中双组分系统进行预测,并进行结构分析及功能预测,旨在从信号调控的角度揭示二者的共生关系.结果表明,德氏乳杆菌保加利亚亚种和嗜热链球菌均含有5～9个双组分系统.其中部分双组分系统涉及调控细菌素合成、蛋白水解能力及建立感受态,推测德氏乳杆菌保加利亚亚种和嗜热链球菌通过以上双组分系统相互协作,进行共生。     

强化混凝SBR工艺处理生活污水实验研究

结合我国生活污水污染源治理现状,利用强化混凝SBR法处理分散式生活污水,通过相关实验,确定该工艺处理生活污水的最佳工况条件和最优运行参数：最佳曝气时间为30.0min,生活污水的进水浓度在一定范围内（400.0mg/L附近）波动时,对处理效果影响不明显,最佳静置沉淀时间为30.0min,最佳滗水时间为5.0s,最佳DO值范围为8.5-9.1mg/L,最佳温度为28.0℃,最佳pH值为6.5-7.5。实验结果表明,强化混凝-SBR法处理分散式生活污水工艺是一种适合我国国情和污水处理技术发展的一项污水处理工艺。     

毒死蜱降解菌的筛选及其降解特性的研究

采用富集培养的方法,从农药厂废水处理池污泥中分离到一株对毒死蜱有较强降解能力的菌株TW-1,TW-1能以毒死蜱为唯一碳源生长.研究了外界因素初始pH、外加碳源质量分数、毒死蜱初始质量浓度、培养温度、接种量对降解菌降解能力的影响,单因素试验结果表明：其最适生长温度为30℃,pH为7.5,毒死蜱初始质量浓度为50 mg/L的条件下,历时72 h,毒死蜱的降解率可达73.97%.     

一株烃降解菌Rhodococcus ruber Z25研究

烃降解茵株Z25分离自大庆油田中新201区块采油污水样,经形态观察和16S rDNA基因序列分析,鉴定为Rhodococcus ruber Z25.该菌株在20～45℃,0～5%盐的质量浓度下生长良好,适宜生长温度为30～40℃,最适盐的质量分数为2.5%.Rhodococcus ruber Z25菌株能以液体石蜡为唯一碳源生长并合成糖脂类生物表面活性剂,发酵48 h,细菌生物量和糖脂产量分别为1.53 g/L和13.22 g/L.经气相色谱对Rhodococcus ruber Z25菌株在好氧和厌氧条件下原油降解的全烃组分分析,结果表明:该茵株在好氧条件下优先降解石油中的轻烃组分,在厌氧条件下优先降解石油中的重烃组分.     

Isolation and identification of Rhodosporidium diobovatum DS-0205 from deep-sea sediment of eastern Pacific Ocean

A facultative heterotrophic strain (DS-0205) was isolated from a deep-sea sediment sample collected at a depth of 5.2 km in the eastern Pacific Ocean, China. Strain DS-0205 is motile helmet-like single cell or pairs, forming hemisphere with the center sunken of variable size. It has a widespread carbon source and nitrogen source, including agarose, citric acid, salicin, D-glucitol nitrate, sodium nitrite and ethylamine. It can grow in the following environment: temperature 4–37 °C, pH 2.0–12.0, tolerance to NaCl⩽15%. Two phylogenetic trees, one based on the ITS and 5.8S rRNA sequences and the other based on the 18S rRNA sequences, unite strain DS-0205(=JCM 0205) to the type strain of Rhodosporidium diobovatum JCM 3787 through a considerable evolutionary distance. These results suggest that strain DS-0205 is a new strain of the Rhodosporidium diobovatum.     

一株秸秆纤维素降解菌株的筛选及其降解特性

纤维素是自然界一种最重要的可再生资源,本文从玉米地土壤中分离出 1 株产纤维素酶能力较强的菌株J-N3。以羧甲基纤维素为唯一碳源的分离培养基和刚果红染色法进行初筛,再将筛选到的菌株进行液体发酵培养并测定酶活。结合形态学特征与分子生物学鉴定结果得知,菌株J-N3为芽孢杆菌属( Bacillus)。并对其酶学性质进行初步研究,得到酶最适pH为6.0时,最适反应温度为50 ℃。玉米秸秆经菌株 J-N3处理20 d 时,秸秆失重率及纤维素分解率分别达到26.22%、31.01%。     

适用于壳幔混合物源成因花岗岩中暗色微粒包体的单斜辉石压力计

花岗岩的壳幔混合物源成因及花岗岩中暗色微粒包体的成因信息是地质学关注的重要研究对象,但至今还没有适用于花岗岩中暗色微粒包体这种基性矿物组合的压力计。依据Patino Douce模拟壳幔岩浆混合过程的试验岩石学研究资料,发现具有基性矿物组合的暗色微粒包体中单斜辉石的Na、Al含量与压力密切相关,得出了压力与单斜辉石中的Na₂O含量、Al₂O₃含量、硬玉分子摩尔分数、契尔马克辉石分子摩尔分数、硬玉分子与契尔马克辉石分子摩尔分数之和的线性关系,以及压力与斜方辉石中Al₂O₃含量的线性关系,进而得出适用于壳幔混合物源成因花岗岩中暗色微粒包体的有效地质压力计。这一压力计为了解壳幔混合物源成因花岗岩浆形成的深度提供了研究手段。将地质压力计应用于西秦岭天水地区车河花岗岩体及其中的暗色微粒包体研究,对了解壳幔混合作用形成的花岗岩等深部地质问题具有重要意义。     

一株降解棉酚的酵母菌培养特征及发酵效果分析

通过比较不同酵母茵在以醋酸棉酚为唯一碳源的固体培养基上的生长状况,筛选出一株在醋酸棉酚培养基中生长较好的产朊假丝酵母1087。酵母茵生长曲线测定结果表明,产朊假丝酵母1087在以醋酸棉酚为唯一碳源的液体培养基中,37℃、170r／min摇床条件下培养20h总菌数达到最大值。以产朊假丝酵母1087为接种剂,以棉粕和红薯渣等为主要原料的固体发酵试验,结果表明,发酵后的样品粗蛋白含量提高了37．4％,棉酚含量下降了55．6％。     

阿尔金山盐湖极端嗜盐古生菌的分离及16S rDNA序列分析

为了研究分析新疆阿尔金山国家自然保护区阿牙克库木湖嗜盐古生菌物种资源,对分离纯化到的极端嗜盐古生菌AJ2和AJ4,采用PCR方法扩增出其16S rRNA基因(16S rDNA),并测定了基因的核苷酸序列.基于16Sr DNA序列的同源性比较和系统发育学分析,发现菌株AJ2是Natrmema属中一个与其他成员不同的新种,命名为Natrinema ajinwuensis sp.nov.;菌株AJ4是Haloarcula属中成员argentinensis的一个亚种,取名为Haloar-cula argentinensis subsp.ajinwuensis.菌株AJ2和AJ4的16S rDNA序列已被GenBank数据库收录,其序列号分别为AY208972和AY208973.     

生物表面活性剂产生菌的筛选及特性研究

从石油污染的土壤中分离出3株生物表面活性剂产生菌,经鉴定菌株31#为假单胞菌属,菌株37#和47#均为芽孢杆菌属.以液体石蜡为唯一碳源液态培养所筛菌株,测定发酵液的菌体密度、pH、表面张力及细胞疏水性.结果表明,菌株31#、37#及47#在发酵过程中的发酵液表面张力最低值分别为49.47、58.00和56.04 mN/...