一株硫酸盐还原菌的分离鉴定及生物学特性研究

从处理硫酸盐废水厌氧折流板反应器（Anaerobic battqe reactor,ABR）的污泥中分离到1株硫酸盐还原菌,对该菌株进行了形态、生理生化特性方面的研究,并对16S rDNA序列进行了分析。该菌株为杆状或弧状,大小为（0．5～0．7）μm×（1．4～1．9）μm,革兰染色阴性,芽胞染色阴性,能运动,具有硫酸盐还原功能。菌株最适生长pH为7．0～8．0,喜中性偏碱环境;初始[SO4^2-]为2000mg／L,OD600nm。值为1．206,SO4^2-去除率达到71％;该菌株能分别利用乳酸、丙酮酸、丁酸、乙酸、乙醇、甲醇、葡萄糖作为电子供体,进行硫酸盐异化还原,乳酸最有利于该菌SO4^2-的去除,SO4^2-去除率为91．4％,其次为丙酮酸,达到51．2％。基于16SrDNA序列同源性构建了系统发育树,结果表明此株菌是属于脱硫弧菌属（Desulfovibrio）的硫酸盐还原菌,与Desulfovibrio具有96．0％的序列相似性。     

不同pH值条件下硫酸盐还原菌组成及硫酸盐还原机制分析

【目的】从海洋沉积物中富集获得硫酸盐还原菌群,改变pH值进行培养,分析pH值对硫酸盐还原性质的影响,明确菌群组成和进行硫酸盐还原功能基因预测,探究硫酸盐还原机制。【方法】分析硫酸盐还原菌群在不同pH值条件下的硫酸盐还原率,在此基础上,利用高通量测序技术和PICRUSt软件分析硫酸盐还原菌群优势菌组成及硫酸盐还原相关基因相对丰度。【结果】硫酸盐还原菌群在不同pH值培养条件下的生长和硫酸盐还原率出现显著变化(P<0.01),在pH 5.0时达到峰值,分别为0.34±0.01和96.52%±0.44%。高通量测序数据显示,pH 5.0时菌群丰富度和多样性最高,优势菌属为假单胞菌(Pseudomonas)和芽孢杆菌(Bacillus),相对丰度较高的基因为同化性硫酸盐还原相关基因。【结论】硫酸盐还原菌富集生长的最适pH 5.0,在此条件下的高硫酸盐还原率由同化性硫酸盐还原途径主导,为揭示硫酸盐还原机制提供了实验支持,并拓宽了硫酸盐还原菌实践应用方面的种质资源。     

一株硫酸盐还原菌的分离鉴定和系统发育分析

从处理硫酸盐废水的厌氧折流板反应器中分离得到一株硫酸盐还原菌D11, 该菌株革兰氏反应阴性, 无芽孢, 菌体杆状稍有弯曲, 宽度在0.6 μm~0.8 μm, 长度在1.8 μm~3.3 μm之间, 有极生单鞭毛, 能运动, 接触酶阳性, 氧化酶阴性。菌株生长的pH范围介于6.0~8.0之间, 最适pH为7.0, 生长温度范围为25°C~37°C, 最适温度为30°C。能够以葡萄糖、蔗糖、乙酸、乳酸、乙醇和丙二醇为唯一碳源生长, 不能利用丙三醇、丁醇、琥珀酸和苹果酸。菌株DNA的G+C含量为62.7 mo     

用硫酸盐还原菌处理重金属废水的研究

介绍了用硫酸盐还原菌处理重金属废水的几种主要方法和原理。硫酸盐还原菌处理含重金属废水主要是通过将可溶性的重金属离子转化成不溶性的金属硫化物、氢氧化物、碳酸盐的方式 ,或直接通过以菌体对重金属离子的吸附完成的。目前研究用硫酸盐还原菌处理重金属废水的主要方法有分批沉淀工艺、吸附处理工艺、化学法和硫酸盐还原菌的混合工艺、全混合处理工艺及硫酸盐还原菌的厌氧上流式污泥床和流化床工艺 ,并对其主要的工艺指标进行了比较。     

用Skerman显微操作技术分离硫酸盐还原菌

本文介绍使用Skerman显微操作技术在非厌气条件下对硫酸盐还原菌进行单细胞分离,这一操作可以代替繁琐费时的常规单菌落分离方法。     

一种肠道硫酸盐还原菌的增菌培养基

目的针对已经分离、纯化的肠道硫酸盐还原菌,建立一种能快速、高效地培养菌体的培养基。方法比较营养丰富的GAM肉汤与常用于培养硫酸盐还原菌的选择性培养基Postgate的培养效果,摸索在GAM肉汤中添加不同浓度的硫酸盐对两种肠道硫酸盐还原菌-Desulfovibrio desulfuricans和Desulfovibrio intestina—zis的培养效果。确定效果最佳的改良GAM培养基配方,并测定在该培养基中D．desulful＇icans的生长曲线。结果与Postgate培养基相比,GAM肉汤能在2d内快速培养D．desulfugicans,但培养至6d时细菌数量大幅降低。在GAM肉汤中添加Na2SO4与FeSO4,在实验浓度范围内,均显著地促进硫酸盐还原菌的生长。在此基础上改良GAM肉汤培养基,培养得到的细菌数量较GAM肉汤显著提高。D．desulfuricans的生长曲线显示,2d时细菌生长达到最高峰,数量可达3．5×10^7 CFU／mL;培养6d,细菌数量为7．3×10^6 CFU／mL。结论基于GAM肉汤改良而得到的增菌培养基,能快速、高效地培养肠道硫酸盐还原菌,为后续进一步研究肠道硫酸盐还原菌的生理功能提供了支持。     

土壤腐蚀网站硫酸盐还原菌的研究

从我国东北、西北、西南和华北的的10多种土壤的苗蚀试验站的钢件周围及腐蚀产物中,分离、纯化了13株硫酸盐还原菌(SRB),测定了它们的形态、生理生化特性及氢化酶活性,据以确定我国广大地区土壤中分布的钢铁晦蚀厌氧腐蚀萄主要为普通脱硫弧菌(Desulfovibriavulgaris)和脱硫脱硫弧菌(D.desulfuricans)。他们对钢的腐蚀速率和其氧化酶活性存在着很好的相关性。     

硫酸盐还原菌及其还原解毒Cr(Ⅵ)的研究进展

硫酸盐还原菌是一类分布广泛, 能进行硫酸盐异化还原反应的严格厌氧菌。利用硫酸盐还原菌可去除环境中的许多污染物, 因而该类细菌在环境污染治理中具有广阔的应用前景。本文介绍了硫酸盐还原菌的生物学特性和代谢特征及其在环境污染治理中的应用, 并对硫酸盐还原菌还原解毒Cr(Ⅵ)及应用于含Cr(Ⅵ)废水处理的研究进展作了综述, 分析了其未来的研究方向。     

硫酸盐还原菌净化工业废水的研究

本文报道了硫酸盐还原菌的菌学特征,以其具有吸附和絮凝作用,使工业废水得到净化。用硫酸盐还原菌处理印染废水,废水的脱色率为92．5％,COD(cr)和BOD5亦达到排放标准。对城市生活废水和含铬的电镀废水亦有很好的处理效果,各项指标分别达到了排放标准,其中净化后的电镀废水还可作为循环水使用。     

硫酸盐还原菌检测与应用研究进展

硫酸盐还原菌是自然界存在最为广泛的细菌之一,近年来该类微生物研究日益受到国内外学者的关注。本文对硫酸盐还原菌的鉴定、量化和应用等方面的研究进展进行综述。     

一株高耐镉硫酸盐还原菌的分离及脱硫性能研究

本研究从镉污染稻田水稻根际土壤中分离、纯化出一株硫酸盐还原菌SRB1-1,并对该菌株的生理生态特征、镉和盐耐受性、16S rDNA、脱硫性能及影响因子进行了系列分析。结果表明,该菌为革兰氏阴性菌,菌体弧状,对镉离子的耐受浓度可达200 mg/L,在2%的氯化钠浓度下仍可生长。对其16S rDNA的序列分析表明该菌株属于脱硫弧菌属(Desulfovibrio)。单因子实验考察温度、pH及SO_4~(2-)浓度对该菌脱硫效率的影响,正交实验确定了该菌最佳脱硫工艺条件及影响因子顺序。结果表明最佳脱硫工艺条件为pH 7.5、温度40℃、SO_4~(2-)浓度为1 000 mg/L、培养时间56 h。     

我国自然湿地的基本特点

我国自然湿地的基本特点王宪礼（中国科学院沈阳应用生态研究所,１１００１５）ＴｈｅＦｕｎｄａｍｅｎｔａｌＣｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆｔｈｅＷｅｔｌａｎｄｓｉｎＣｈｉｎａ．ＷａｎｇＸｉａｎｌｉ（ＩｎｓｔｉｔｕｔｅｏｆＡｐｐｌｉｅｄＥｃｏｌｏｇｙ,...     

Anaerobic Biodegradation of Poly-3-Hydroxybutyrate (PHB) by Sulfate Reducing Bacterium Desulfotomaculum sp.

Poly-3-hydroxybutyrate (PHB) film pieces were degraded by sulfate reducing Desulfotomaculum sp. incubated under anaerobic laboratory conditions. Degradation started with adherence of the microbial cells and followed by formation of black colonies on the film surface. Scanning electron microscopic (SEM) observations revealed the presence of bacteria and formation of small holes on the film. After 60 days of incubation at 30°C, 10 % weight loss in polymer and 13 % sulfate reduction in the medium was observed. According to gel permeation chromatography (GPC) analysis, the molecular weight of the PHB decreased after 30 days and did not decrease further at a more extended incubation period. Loss of weight of PHB does not seem to be correlated with molecular weight decrease.     

感染根管的厌氧菌培养结果分析

从64只感染根管中的58只根管分离到144株无芽胞厌氧菌,其中类杆菌54株,厌氧性链球菌23株,韦荣氏球菌17株,真杆菌11株,梭杆菌10株,放线菌8株,双岐杆菌2株,消化链球菌和消化球菌19株。40只根管为厌氧菌和兼性厌氧菌或需氧菌混合感染,18只根管和6只根管分别为单独厌氧菌和兼性厌氧菌感染。33只根尖周炎根管分别采集牙髓和根尖渗出物样本进行培养,实验结果表明牙髓样本中革兰氏阳性厌氧杆菌检出率较高,根尖渗出物中以产黑素类杆菌属的细菌检出率较高。根尖周炎和牙槽脓肿患者的感染根管中产黑素类杆菌属的细菌检出率明显高于蜂窝组织炎患者。     

Enhancement of sulfate reduction activity using granular sludge in anaerobic treatment of acid mine drainage

Three laboratory-scale, upflow anaerobic reactors were operated for about 250 d to determine the effect of activated granular sludge with high density of sulfate reducing bacteria in the treatment of artificial acid mine drainage. Sulfate reducing bacteria in the granular sludge taken from the upflow anaerobic sludge blanket reactor were 1–2×10⁶ c.f.u. g^–1, which is at least 10 times higher than that of organic substrates such as cow manure and oak compost. The reactors with granular sludge effectively removed over 99% of heavy metals, such as Fe, Al, Cu, and Cd during the experiment. This result suggests a feasibility of the application of granular sludge as a source of sulfate reducing bacteria for the treatment of acid mine drainage.     

Isolation of Nitrogen Fixing Bacteria from Fungus Termites

Biological nitrogen fixation by the microorganisms in the gut of termites is one of the singularly important symbiotic processes, since termites invariably thrive on nitrogen poor diet. Two isolates of free living aerobic and facultative anaerobic N fixing bacteria were obtained from the guts of fungus cultivating termite, Macrotermes sp. Among the total bacterial isolates from termite gut, the per cents of N fixing aerobes viz., Azotobacter and Beijerinckia spp were 49% and 37% from the salivary gland while facultative N fixing anaerobe viz., Klebsiella and Clostridium contributed (51% and 93%). The free living aerobic bacteria were identified as Azotobacter spp (19 x 10⁴ CFU mL^‐1) and Beijerinckia (13.2 x 10⁴ CFU mL^‐1) from the salivary gland of the termite; interestingly, foregut, mid gut and hind gut registered a low population of these bacteria. The isolates of Azotobacter were smooth, glistening, vicid in nature, rods, gram negative and cyst forming. Isolates of Beijerinckia sp. produced copious slime, tenacious, rods, gram negative with no cyst formations. Both the isolates emitted green fluorescence and produced acid. Facultative N fixing anaerobes were harbored in the hind gut. The isolates were identified as Klebsiella (20 x 10⁴ CFU mL^‐1) and Clostridium pasteurianum 39.1 x 10⁴ CFU mL^‐1. Klebsiella were straight rods arranged singly or in pairs, non‐motile, gram negative, whereas Clostridium pasteurianum was viscoid, motile with terminal spores. A positive correlation was observed between the extractable polysaccharides of these isolates and soil aggregation. The aggregates formed by the isolates increased soil aeration, porosity, water holding capacity and helped in better plant growth. Thus, the gut microflora of termite, apart from harnessing nitrogen from the atmosphere, also helps improving soil fertility.     

大豆根际土壤中氢氧化细菌的分离、筛选和基本特征

土壤中的氢氧化细菌能够利用土壤中的H2为能源并同化CO2,增加其种群数量并促进作物生长.采用气体循环培养体系(持续通氢气装置),通过电解水的方式产生H2,与通入的空气混合,形成流速为280ml.min-1、含H2量为41.6～125μmol.L-1的混合气体.采用矿质盐固体培养基,在适当的H2、O2和CO2下以H2作为唯一能源分离氢氧化细菌.采用此方法从大豆根际土壤样品中分离出40余株细菌,对其进行耗氢能力测定表明,有20株菌具有氧化氢功能和自养生长能力,初步判断这20株菌为氢氧化细菌,并测定了菌落形态及生理生化特征.     

Isolation,Characterization and Kinetics of Perchlorate Reducing Magnetospirillum Species

Perchlorate reducing bacteria reduce perchlorate to chlorate (ClO₃?), which, in turn, is reduced to chlorite (ClO₂?) and ultimately to chloride (Cl^?). Magnetospirillum strains are reported to use chlorate/perchlorate as electron acceptors. This study describes the perchlorate reducing property of strain VITRJS5, a Magnetopsirillum isolated from freshwater sediment collected from Chelur freshwater lake, Kerala, India. The strain was microaerophile and was phylogenetically related to a Magnetospirillum sp., a member of the α-subclass of the class Proteobacteria. The placement of the isolate in the genus Magnetospirillum has further confirmed the presence of four key magnetosome membrane genes. PCR amplification and phylogenetic analysis of central metabolic genes such as nifH (nitrogenase) and cbbM (type II RubisCo) displayed the highest similarity (97% and 81%, respectively) with Magnetospirillum sp. BB-1 The growth kinetic parameters of the isolate were studied with acetate as the electron donor in batch experiments. Monod's substrate utilization model has been established with oxygen, nitrate and perchlorate as electron acceptors separately. The maximum specific growth rate (µ_max) and half-saturation constant (k_s^conc) for the bacterium varied while utilizing different electron acceptors. The maximum specific growth rate was 0.226, 0.190 and 0.096 per hour and half-velocity constant K_s was 25.09, 33.36 and 65.37 mg acetate/l for oxygen, nitrate and perchlorate, respectively. The reduction of perchlorate has been analyzed using kinetic studies of the substrate uptake by the bacteria and the half-velocity constant K_s was found to be 52.8 mg/l. The results indicate that the strain VITRJS5 effectively reduces perchlorate by using it as an electron acceptor.