功夫菊酯降解菌 GF-1 的分离鉴定及其降解特性研究

从农药厂废水处理池的活性污泥中分离到一株功夫菊酯高效降解菌 GF-1,根据表型特征、生理生化特性和 16S rDNA 序列同源性分析,将 GF-1 鉴定为芽孢杆菌属(Bacillus sp.).GF-1 能以功夫菊酯为唯一 C 源进行生长,72 h 对100 mg/L的功夫菊酯的降解率达 85%.GF-1 降解功夫菊酯的最适温度为 30℃,最适 pH 为 7.0,该菌降解功夫菊酯的速率与初始接种量呈正相关.GF-1 投加土壤,可以提高土壤中功夫菊酯的降解速率.通过吖啶橙与升温法对质粒消除,结果表明 GF-1 的降解功能与质粒相关.     

苯磺隆降解菌的分离鉴定和特性研究

为解决苯磺隆残留问题,本试验利用富集驯化培养分离法,从连续多年使用苯磺隆的田间土壤中,分离筛出一株能以苯磺隆为唯一碳源、氮源生长的降解菌。通过形态学、生理生化测定及16S r DNA序列系统发育分析,鉴定该菌株为产碱杆菌。抗生素敏感试验和底物敏感试验表明:降解菌株BHL对试验浓度范围内的所有供试抗生素都表现为敏感,其中对硫酸阿米卡星最为敏感;菌株BHL可以很好的利用试验所用磺酰脲类除草剂和有机磷农药,同时还可以利用部分芳香族化合物。本研究为功能农药残留降解菌的研究提供了理论基础。     

基于构建微生物传感器的甲基对硫磷降解菌的分离鉴定及其降解特性研究

有机磷农药是目前环境中残留量最多的农药之一,对其残留量的检测及降解机制的研究对于环境污染及生态修复具有重要意义。微生物传感器由生物学元件与换能器构成,因具有成本低廉、易于微型化及选择性高等特点而被广泛应用于各种生化物质的分析和检测。本文从长期受农药污染的土壤中分离出4株能以甲基对硫磷为碳源生长的菌株,根据形态特征和16S r RNA基因序列同源性分析,对4株降解菌进行鉴定,利用高效液相色谱测定降解率,选取降解率最高的1株菌进行降解机制研究,以期将其应用于测定环境中甲基对硫磷残留的电位型微生物传感器的构建。结果表明,在甲基对硫磷初始浓度50 mg·L-1、30℃、p H 7.0的培养条件下培养7 d,4株菌对甲基对硫磷的降解率均在78%以上,其中1株菌的降解效率可达100%。16S r RNA基因序列测定表明,该菌株属于克雷伯氏菌属,命名为Klebsiella sp.MP-6。利用液相色谱-质谱联用对其降解产物的研究表明,菌株MP-6水解甲基对硫磷主要产生二甲基硫代磷酸(dimethyl thiophosphoric acid,DMTP)和对硝基苯酚(p-nitrophenol,PNP),极少部分PNP通过产生4-硝基邻苯二酚(4-nitrocatechol,4-NC)和1,2,4-苯三酚(1,2,4-BT)进一步代谢。结果表明,基于测定中间产物对硝基苯酚(p-nitrophenol,PNP)的电位响应信号,该菌株适用于构建测定海水及土壤等环境中有机磷农药的微生物传感器。     

一株热带芽孢杆菌的分离鉴定及促生作用研究

为了筛选高效植物根际促生菌株,分析菌株促生应用潜力,为微生物肥料的研发提供宝贵的菌种资源。采集了海南省乐东黎族自治县的根际土壤,采用稀释涂布法分离筛选促生菌株,研究其产吲哚乙酸(IAA)、铁载体、蛋白酶、溶磷的能力,通过16S r RNA基因系统发育分析和全基因组特征对新分离菌株进行物种鉴定。分离得到一株产多种促生活性物质的菌株S03,基于16S rRNA基因和系统发育树分析结果表明,新分离菌株S03与NR157736热带芽孢杆菌(Bacillus tropicus)1A01406亲缘关系最近,结合全基因测序结果,确定菌株S03为Bacillus tropicus。Bacillus tropicus S03基因组全长5.42 Mb,碱基对G+C含量为36.02%,共编码5666个基因。通过GO数据库对比分析,S03具备促生物质(IAA、铁载体等)合成相关的基因。Bacillus tropicus S03的促生潜力良好,IAA产量为45.73 mg·L^-1,溶解无机磷能力为82.30 mg·L^-1,同时还具备产蛋白酶和铁载体的能力,Bacill...     

四环素类抗生素降解菌的分离与鉴定

为了获得四环素类抗生素的高效降解菌,从长期受四环素类抗生素污染的土壤中分离、重复驯化筛选得到6株对四环素类抗生素具有降解能力的菌株;采用高效液相色谱法研究了6株降解菌的降解效果,并通过形态、生理生化特征及16S rDNA序列分析对其进行鉴定。结果表明,菌株TJ-2#对土霉素、四环素和金霉素3种四环素类抗生素的降解效果最好,降解率分别为58.3%、63.9%和65.5%,TJ-6#其次;6株降解菌均能以四环素类抗生素作为唯一碳源生长。经形态、生理生化特征及16S rDNA鉴定,菌株TJ-2#为木糖氧化无色杆菌(Achromobacter sp.),TJ-6#为枯草芽胞杆菌(Bacillus sp.)。本研究结果对四环素类抗生素的生物降解具有一定的现实意义。     

4株苯磺隆降解菌的分离鉴定及其生长特性

从长期受农药苯磺隆污染的土壤中通过采用富集培养分离技术得到4株以苯磺隆为唯一碳源生长的细菌,分别将其命名为B1、B2、B3和B4。通过观察这4种菌株的形态学特征,研究其生理生化特性以及分析其16S rDNA序列,初步鉴定菌株B1为铜绿假单胞菌(Pseudomonas aeruginosa),B2为戴尔福特菌(Delftia sp.),B3为微杆菌(Microbacterium sp.),B4为产碱杆菌(Alcaligenes sp.)。并通过研究温度、初始pH值、接种量、苯磺隆初始浓度、培养基体积、氮源、碳源、Mg2+浓度等因素对4种菌株生长情况的影响,确定了菌株的最佳生长条件。结果显示,B1菌株的最适温度为35℃,其他3株菌株均为30℃。菌株B3最适pH为8.0,其余3株菌株均为pH7.0。B1和B3菌株最适接种量为15%,B2和B4最适接种量为10%。菌株B3最适苯磺隆初始浓度为100mg·L-1,其余菌株最适苯磺隆初始浓度均为200mg·L-1。4株菌株最适培养基体积均为75mL,最适氮源均为硝酸铵,最适碳源均为葡萄糖。B2菌株最适Mg2+浓度为100mg·L-1,其余3株菌株均为200mg·L-1。B1和B4菌株最适NaCl浓度为20g·L-1,B2菌株NaCl浓度为5~30g·L-1,B3菌株最适NaCl浓度为50g·L-1。该结果为利用微生物对农药苯磺隆污染的土壤进行原位生物修复提供理论依据。     

一株烟草秸秆降解菌的分离、鉴定及酶学性质研究

从皖南地区烟稻轮作田土壤中经CMC-Na初筛获得5株纤维素降解菌,经DNS法测定纤维素酶活性复筛得到一株降解活性较高的降解菌YC-2。根据该菌16S r DNA序列比对结果,结合形态和生理生化特征,确定YC-2为枯草芽孢杆菌(Bacillus subtilis)。对YC-2酶学性质进行相关研究,并分析YC-2对烟碱的耐受情况及对烟草秸秆的降解情况,结果表明:在7天内,YC-2对烟草秸秆降解率为10.14%;酶学特性表现为最适反应温度为60℃且在15~60℃之间具有稳定性;最适反应pH为7.0,在pH 4.0~7.5范围内稳定性较好;YC-2在浓度为1~2 g/L烟碱中能快速生长,而在高浓度的烟碱中生长受到抑制。因此,菌株YC-2产纤维素酶活性较高、相对耐热耐碱且对烟杆有一定分解作用,通过进一步诱变选育和发酵条件优化有较好的田间应用潜力。     

猪毛角蛋白降解菌的分离筛选及其降解特性研究

为了筛选能高效降解猪毛角蛋白的微生物,该研究利用猪毛角蛋白为唯一碳氮源的培养基从土壤中分离角蛋白降解菌,并对其菌种分类及降解角蛋白的特性进行了研究。通过驯化共筛选到6株能够降解猪毛角蛋白的菌株,经过7 d发酵培养,菌株X-3对猪毛角蛋白的降解率达77.3%,降解效果最佳。结合菌株形态特征、生理生化特征及16S rDNA发育进化树分析,初步鉴定该菌株为凝结芽孢杆菌(Bacillus coagulans)。菌株X-3是一株广谱的角蛋白降解菌,对猪毛、羊毛、鸡毛、鹅毛、鸭毛的降解率均大于60%。该菌株在角蛋白底物作用下可产生角蛋白酶和二硫键还原酶,且酶活与猪毛角蛋白降解率变化存在显著的正相关性,表明菌株X-3产生的角蛋白酶和二硫键还原酶在角蛋白降解中起到非常关键的作用。在降解过程中,产生了大量的可溶性蛋白,二硫键中的硫也随之转化为硫酸盐、亚硫酸盐和巯基化合物,其中硫酸盐是主要的转化形式。该菌株的分离筛选丰富了猪毛角蛋白降解菌的微生物资源库,在氨基酸饲料生产中具有潜在的应用价值。     

污染土壤中原位阿特拉津降解菌的分离和鉴定

为克服传统富集培养分离降解菌的局限性,直接将长期受阿特拉津污染的土壤稀释后,涂布于加有土壤浸出液和阿特拉津农药的平板,分别从两个采自不同地区的污染土壤中各分离了一株高效广谱降解菌AG1和ADG1：它们能以阿特拉津为唯一碳源、氮源和能源生长,能分别在44h和48 h内降解1 000mg L^-1的阿特拉津,降解率100%;它们还能以扑草净、西玛津等三嗪类除草剂为唯一氮源生长.16S rDNA核苷酸序列分析结果表明菌株AG1与ADG1都与节杆菌属（Arthrobacter）的细菌有高度同源性,结合两株菌的形态特征及生理生化特征,将它们鉴定为Arthrobacter spp..PCR扩增两株菌的降解基因,结果表明它们的降解基因都是trzN和atzBC的组合,这是国内首次报道具有该基因类型的阿特拉津降解菌.     

百菌清降解菌株H4的分离与表征及其修复污染土壤的潜能研究

A chlorothalonil(CTN)-degrading bacterial strain H4 was isolated in this study from a contaminated soil by continuous enrichment culture to identify its characteristics and to investigate its potential for remediation of CTN in contaminated soil. Based on the morphological, physiological and biochemical tests and 16 S r DNA sequence analysis, the strain was identified as Stenotrophomonas sp. After liquid culture for 7 d, 82.2% of CTN was removed by strain H4. The isolate could degrade CTN over a broad range of temperatures and p H values, and the optimum conditions for H4 degradation were p H 7.0 and 30℃. Reintroduction of the bacteria into artificially contaminated soil resulted in substantial removal of CTN( 50%) after incubation for 14 d. Soil samples treated by H4 showed significant increases(P 0.05) in soil dehydrogenase activity, soil polyphenol oxidase activity, average well-color development obtained by the Biolog Eco plate TM assay and Shannon-Weaver index, compared with the control. Strain H4 might be a promising candidate for application in the bioremediation of CTN-contaminated soils.     

Isolation and Characterization of a Bensulfuron-Methyl-Degrading Strain L1 of Bacillus

The objectives of this study were to isolate a bensulfuron-methyl (BSM)-degrading strain of Bacillus spp. and to eval-uate its effectiveness in remediation of a BSM-contaminated soil. A BSM-degrading bacterium, strain L1, was successfully isolated in this study. Strain L1 was identified as Bacillus megaterium based on its morphological, physiological, and biochemical properties, G+C content, phylogenetic similarity of 16S rDNA, and fatty acid composition. Two experiments were used to examine BSM degradation by strain L1. When BSM was used as a sole carbon source in a mineral salt medium, the average degradation rate of BSM by strain L1 was 12.8%, which suggested that the strain was able to utilize BSM as a sole carbon and energy source. Supplement of yeast extract (200 mg L-1 ) significantly (P ≤ 0.01) accelerated the degradation of BSM by strain L1. Almost complete degradation (97.7%) of BSM could be achieved in 84 h with addition of yeast extract. In addition, in a sterile soil with 50 mg L-1 BSM, BSM degradation rate by strain L1 was 94.3% in 42 d, indicating the potential of using microbes for the remediation of BSM-contaminated soils in fields.     

灭多威降解菌mdw-1的分离和降解特性研究

Methomyl, an extremely toxic pesticide, is widely used in agriculture. A strain named mdw-1 capable of degrading methomyl rapidly was successfully isolated from activated sludge in this study. It could utilize methomyl as the sole carbon or nitrogen source. The optimal temperature and medium pH for its growth and methomyl biodegradation were 30-C and 7.0, respectively. It was identified as a Paracoccus sp. according to its morphological features, physiological and biochemical characteristics, and phylogenetic analysis based on the sequence of 16S rDNA. Gas chromatography-mass spectrometry (GC-MS) analysis showed that methomyl could be completely transformed to S-methyl-N-hydroxythioacetamidate in 10 h of incubation with the isolate mdw-1.     

7株解有机磷细菌的分离和鉴定

从土壤中分离筛选出7株解有机磷的微生物。对这7株解磷细菌进行了形态、生理生化性状测定及16SrDNA序列分析(GenBankaccessionNo:S2,AY651922;S3,AY661923;X1,AY651925;Y1,AY651924;H1,AY663435;H2,AY663436andHe,AY663436)。其中S2、S3、X1和He属于假单胞菌属(Pseudomonas),Y1属于芽孢杆菌属(Bacillus),H1属于不动杆菌属(Acinetobacter),H2属于寡养单胞菌属(Stenotrophomonas)。进一步通过G C含量和DNA-DNA杂交研究,结果表明,S2、S3和X1为产碱假单胞菌(Pseudomonasalcaligenes),Y1为蜡状芽孢杆菌(Bacilluscereus)。     

一株敌敌畏降解菌DDV-1(Ochrobactrium sp.)的分离鉴定及其降解特性的研究

Soil organic carbon （C） and total nitrogen （N） pools of a Chinese fir （Cunninghamia lanceolata （Lamb.） Hook.） （CF） forest, and an evergreen broadleaf （EB） forest located in mid-subtropical, southeastern China, were compared before clearcutting, with the effect of slash burning on organic C and total N in the top 10 cm of soil before and after burning also being evaluated. Prior to clearcutting CF forest had significantly lower （P 〈0.05） organic C and total N in the soil （0-100 cm） compared to EB forest with approximately 60% of the C and N at the two forest sites stored at the 0 to 40 cm soil. In post-burn samples of the 0-10 cm depth at 5 days, 1 year, and 5 years for CF and EB forests, significantly lower levels （P 〈0.05） of organic C and total N than those in the pre-burn samples were observed. Compared to the pre-burn levels, at post-burn year 5, surface soil organic C storage was only 85% in CF forest and 72% in EB forest, while total N storage was 77% for CF forest and 73% for EB forest. Slash burning caused marked long-term changes in surface soil C and N in the two forest types.     

利用高通量测序对三江平原小叶章湿地土壤细菌多样性的研究

利用黑龙江省科学院自然与生态研究所三江平原野外实验研究站内3个不同小叶章生态类型湿地土壤样品,直接提取土壤微生物总DNA,应用Miseq测序技术对16S rDNA进行序列测定和分析。结果表明:不同小叶章湿地土壤细菌群落结构发生了显著变化,土壤细菌多样性和丰富度随着土壤含水率的增加而降低。草甸化湿地和沼泽化草甸湿地优势种群为酸杆菌,变形菌次之;沼泽化湿地优势种群为变形菌,酸杆菌次之。土壤含水率的增加减少了酸杆菌的分布,而增加了变形菌的分布。16S rDNAheatmap分析则表明,湿地水位的变化对酸杆菌和变形菌的群落结构影响最大。     

Identification and characterization of rhizobacteria isolated by enrichment culture on spinach roots

Rhizobacteria can be used for biological control and environmental restoration. In this study, we performed enrichment culture of rhizobacteria, identified isolates, and investigated the physiological properties of the bacterial isolates. Five bacteria differing in their colony morphology were isolated from spinach roots as enriched rhizobacteria. Four isolates were identified by sequencing of 16S rDNA as β and γ-Proteobacteria; 16S rDNA sequencing was not completed on one isolate. Based on microscopic observation, we determined that at least two types of bacteria differing in their morphology co-existed in this isolate, and that it may not be possible to culture the two types separately. Based on tests of substrate utilization, we could not find the characteristics that were common to the isolates. One of the five isolates was inoculated into non-sterile soil, and we examined its root-colonizing ability. The test strain which was not detected in the non-rhizosphere soil, accounted for about 20% of the total bacteria on the roots. These results suggested that enrichment culture might be useful for isolating bacteria with a high root-colonizing ability     

一株高效溶解钾长石芽孢杆菌的分离鉴定与生物学特性研究

从风化的钾质粗面岩表面分离筛选到1株高效风化钾长石的芽孢杆菌E31菌株,通过菌株的生理生化特征并结合菌株16S r DNA序列分析,E31菌株被鉴定为苏云金芽孢杆菌(Bacillus thuringiensis)。同时对E31菌株溶解钾长石的效应与机制以及生物学特性进行了研究。结果表明,E31菌株能风化钾长石并释放出其中的元素,28℃振荡培养不同时间,接菌处理发酵液中可溶性K、Fe、Ca、Al含量分别比对照提高了19.6%~25.6%、1~12.5倍、10.4%~47.2%和1.2~4.5倍。在钾长石存在条件下接菌处理发酵液pH为3.62~3.80,发酵液中葡萄糖酸含量达61~1 794 mg/L,发酵液细胞数量达(8.7~16.1)×10~6 cfu/ml,表明菌株可以通过代谢产生的有机酸来加速对钾长石的分解作用。另外,E31菌株能够合成生长素和铁载体,E31菌株对温度、pH和盐浓度具有较强的耐受性。     

二(2-乙基己基)邻苯二甲酸酯降解菌的分离和鉴定及其在污染土壤生物修复中的作用

Di-（2-ethylhexyl） phthalate（DEHP） is a high-molecular-weight phthalate ester（PAE） that has been widely used in the manufacture of polyvinylchloride and contributes to environmental pollution.The objectives of the present study were to isolate a DEHP degrader that can utilize DEHP as a carbon source and to investigate its capacity to biodegrade DEHP in both liquid culture and soil.A bacterial strain WJ4 was isolated from an intensively managed vegetable soil,which was contaminated with PAEs.The strain WJ4 was affiliated to the genus Rhodococcus and was able to remove DEHP from soil effectively.A period of only 7 d was required to degrade about 96.4%of DEHP(200 mg L^-1) in the liquid culture,and more than 55%of DEHP(1.0 g kg^-1) in the artificially contaminated soil was removed within 21 d.Furthermore,Rhodococcus sp.strain WJ4 had a strong ability to degrade DEHP without additional nutrients in liquid minimal medium culture and DEHP-contaminated soil and to degrade the homologue of DEHP in both liquid culture and soil.Strain WJ4 represents a novel tool for removing PAEs from contaminated soils and it may have great potential for application in the remediation of environmental pollution by PAEs.     

尼古丁降解菌L1的分离鉴定与降解特性分析

通过对分离于烟草叶片的154株具有降解尼古丁细菌菌株筛选，获得能高效降解尼古丁的L1菌株。通过形态观察，16S rDNA序列分析和生理生化测定将其鉴定为Bacillus simplex。菌落生长密度测定和高压液相色谱分析表明， L1菌株最适生长尼古丁浓度为1g/L，随着菌落密度增加，尼古丁降解效率逐渐升高，36 h最高降解率达到75.0%。而低尼古丁含量不利于L1菌株的生长，过高尼古丁含量对L1菌株的生长和降解效率具有反馈抑制作用。菌株L1降解尼古丁过程中无色素产生，说明其尼古丁代谢途径有别于节杆菌。