一株嗜盐脱硫菌的筛选及其脱硫特性的研究

从晒盐场污泥里筛选出一株嗜盐脱硫菌株ZTLH,经分子生物学方法鉴定为Halothiobactllus kelly 菌属.H.kelly ZTLH 在高浓度 Na+(1.8 mol/L)、pH=8.0～10.5、36～39℃条件下,对S2-去除速度最高可达20 mmol/(L·h).以氧化还原电位为控制指标时的脱硫效果优...     

一株厌氧嗜盐菌的鉴定

从冬尖腌制品中分离到一株厌氧嗜盐菌（SEM）,该菌为革兰氏阴性杆菌,大小为0．5×6.0μm,专性厌氧,不运动,不形成芽孢,生长需要8％～25％NaC1,最适生长盐浓度为12．50～17．50,能利用多种糖和醇,发酵葡萄糖产生丙酸和已酸。它应归属于严格厌氧嗜盐菌Haloanaerobe,但与已报道的几个种有较大差异,是否为新种,还有待于进一步研究。     

嗜盐嗜碱杆菌属的一个新种

从内蒙古自治区哈马台碱湖分离到一株多形态嗜盐嗜碱菌(编号HAM—2),其生长的NaCI浓度范围为12％～30％,最适17.5％;生长的pH范围为7.8～10.4,最适pH9.0～9.5。革兰氏染色阴性。细胞为不规则杆状、椭圆形、三角形等多形态,细胞大小为1.0～2.0×2.0～5.Oμm。该菌株主要极性脂是磷脂酰甘油磷酯(PGP)和磷脂酰甘油(PG),还含有一种未知的次要磷脂成分(PL4)。DNA中G+C含量为59.5mol％。根据这些特征,菌株可归入嗜盐嗜碱杆菌属,又根据细胞形态和极性脂组份不同于该属正式承认的三个种,因此,鉴定此菌株为嗜盐嗜碱杆菌属(Natronobacterium)的—个新种,定名为内蒙古嗜盐嗜碱菌(Natronobacterium innermongoliae Sp.nov.)。     

耐盐硫氧化菌的筛选、鉴定及脱硫性能研究

【目的】从典型自然环境中筛选耐盐高效硫氧化菌,研究其生长特性,并进行初步脱硫实验。【方法】以硫代硫酸钠为唯一能源底物的培养基富集脱硫菌,经过3次平板划线培养、纯种分离后得到纯种培养。经过革兰氏染色、平板菌落形态观察及形态学特征研究,并结合16S rRNA基因序列分析及分子系统发育树的构建结果,确定菌株的种类。【结果】从上海外高桥某发电厂冷却水池中筛选分离出一株硫代硫酸盐去除率高、耐盐性较强的细菌,命名为CYJN-1。该菌为革兰氏阴性菌,短杆状,鉴定为那不勒斯菌(Halothiobacillus neapolitanus)。H. neapolitanus CYJN-1具有较强适应盐度变化的能力,菌株生长的盐度范围为0?5% (NaCI,质量体积比)。菌株最适生长条件为：温度30 °C、pH 7.0、底物浓度为20 g/L。在此条件下,该菌对硫代硫酸钠的去除率可达98%。【结论】H. neapolitanus CYJN-1耐盐性较强,硫代硫酸盐去除率高,在生物脱硫、生物冶金等领域都具有潜在的应用前景。     

盐地碱蓬内生中度嗜盐菌

植物内生菌已经成为我国微生物领域研究的热点之一[1],对植物内生细菌的研究不仅丰富了内生菌的生理类群及数量,而且探索了内生菌与植物的相互关系;同时也发现了一些新分类地位的菌株。目前,关于植物内生极端微生物的研究较少,本刊2010年第2期刊登了崔春晓、夏志洁等发表的文章"盐地碱蓬内生中度嗜盐菌的分离与系统发育多样性分析"[2],作者根据盐地碱蓬内生境高盐的特点,从中不仅     

一株嗜盐菌新种的分离与鉴定

从舟山册子岛船舶压载水泥样中分离到一株细菌S3-22,其与已知细菌的16S rDNA序列相似性低于97%,G+C mol%为54.9 mol%,主要脂肪酸iso-C17:1ω9c(24.99%),细胞醌型为甲基萘醌MK-5。革兰氏染色阴性,最适生长条件为30～37℃、pH7、3%NaCl。嗜盐,氧化酶、接触酶、淀粉酶、酯酶呈阳性,可还原硝酸盐。依据其16S rDNA序列相似性、系统发育学分析及细胞与分子水平的鉴定表明,该菌是Kordiimonas属的一个新种,菌株S3-22的16S rDNA序列登陆号为FJ847942。     

嗜盐菌的嗜盐机制

嗜盐菌是生活在高盐环境中的细菌。它们的细胞结构和生理机能特殊,要求有高盐浓度维持其生存;同时,它们的细胞膜结构和细胞内的溶质,都能适应高盐环境。     

表面活性剂对嗜盐嗜碱硫碱弧菌D301生成及利用硫颗粒的影响

【背景】微生物脱硫是脱除气体中硫化氢的一种有效方法,其中,硫颗粒的生成与代谢是控制生物脱硫效率的关键,但目前相应的控制方法很少。【目的】研究不同种类表面活性剂对硫碱弧菌D301生成及利用硫颗粒的影响。【方法】通过摇床培养,利用X射线衍射、冷场发射扫描电镜、能谱分析及傅里叶红外光谱对硫颗粒进行表征。【结果】单质硫主要以S8形式存在,吐温-80和十二烷基磺酸钠(Sodium Dodecyl Sulfate,SDS)的添加对硫颗粒的形态及生成量影响明显。对照组中生成的硫颗粒呈规则球形,光滑完整,其表面附着蛋白质等生物大分子;加入0.01 g/L吐温-80后,硫颗粒呈长杆状、颗粒增大、利用速率减慢;加入0.3g/L的SDS后,硫颗粒呈短棒状、生成量减少、利用速率加快,同时延缓了硫碱弧菌D301的衰亡。【结论】添加表面活性剂可以改变硫颗粒形态并且影响其利用,是一种调控硫颗粒生成和代谢的有效手段。     

嗜盐小盒菌属新种的鉴定

从新疆盐湖分离纯化到3株多形态嗜盐菌(编号为A_5,B_ 2和B-B_2).以《伯杰氏系统细菌学鉴定手册》第3卷(1989年)为主要依据,根据极性脂分析,这3株菌可归入嗜盐小盒菌属(Haloarcula).又根据细胞形态特征和生理生化特性,这3株菌不同于该属中现在正式承认的两个种而成为一独立的类群,建议为嗜盐小盒菌属中的一个新种,命名为艾丁嗜盐小盒菌(Haloarcula aidinensis sp.nov.).以A_5菌株作为模式株.     

一株产碱极端嗜盐杆菌

从青海省大柴旦盐湖中分离到一株极端嗜盐杆菌。该菌株在培养过程中产碱,革兰氏阴性,细胞杆状,0．7-1.0×2-3μm,极生鞭毛运动,绝对好氧,以氨基酸作唯一碳源。不利用碳水化合物,生长所需盐(NaCl)浓度在1 2％以上,最适盐浓度为l 8％。生长pH范围6-l0,最适pH9。MgSO4·7H2Oo-3％对生长无明显影响。细胞蛋白质酸性,不含二氨莲庚二酸和胞壁酸,含甘油二醚键化合物,不具有色素。根据以上特征,将该菌株定为一个新种,定名为产碱嗜盐杆菌(Halobocierium haloalcaligenum n.sp.)。     

冲绳海槽热液区可培养硫氧化细菌多样性及其硫氧化特性

冲绳海槽热液区独特的地质环境孕育了特殊的生物群落,硫氧化细菌作为生物地球化学循环的重要参与者在热液生态系统中发挥着至关重要的作用。【目的】通过硫氧化菌株的分离培养揭示冲绳海槽热液区可培养硫氧化细菌的多样性和硫氧化活性。【方法】采用多种培养基对冲绳海槽热液区不同沉积物样品中的硫氧化细菌进行富集培养和分离纯化;利用16S rRNA基因序列确定硫氧化细菌的分类地位并进行系统发育分析;采用碘量法对典型硫氧化菌株硫氧化活性进行检测。【结果】本研究从冲绳海槽热液区样品中共分离鉴定85株硫氧化细菌,分属于α-变形菌纲、γ-变形菌纲、放线菌门和厚壁菌门,优势属为氢弧菌属(Hydrogenovibrio)、拉布伦氏菌属(Labrenzia)、深海海旋菌属(Thalassospira)和海杆状菌属(Marinobacter)。硫氧化活性检测结果表明,7株典型硫氧化菌株对硫代硫酸钠的降解活性介于31%–100%之间,其中泰坦尼克号盐单胞菌SOB56 (Halomonas titanicae SOB56)、南极海杆状菌SOB93(Marinobacter antarcticus SOB93)、印度硫氧化粗杆菌SOB107 (Thioclava indica SOB107)和嗜温氢弧菌CJG136 (Hydrogenovibrio thermophiles CJG136)可以完全降解硫代硫酸钠。【结论】冲绳海槽热液区可培养硫氧化细菌的多样性丰富,为研究该热液区的硫循环过程提供了实验材料和理论基础,多种硫氧化活性菌株的获得极大地丰富了菌种资源,为探究深海热液区硫循环的能量代谢途径和分子机制奠定基础。     

Screening, identification and kinetic characterization of a bacterium for Mn(II) uptake and oxidation

Following sample collection and screening at a number of Mn-associated mine sites in Northern Australia, a microbial strain was selected for its enhanced rate of Mn uptake. The strain was identified by phylogenetic analysis as a Rhizobium sp. Kinetic studies of Mn(II) uptake and oxidation by this strain in glucose-based media established that the uptake of Mn(II) was much greater than the conversion of Mn(II) to Mn oxide. Chemical analysis and scanning electron microscopy confirmed the production of significant amounts of polysaccharides by this strain. These polysaccharides may play a role both in enhancing Mn(II) accumulation and in minimizing Mn oxide production.     

Characterization of sulfur oxidation by an autotrophic sulfur oxidizer,Thiobacillus sp. ASWW-2

An autotrophic sulfur oxidizer,Thiobacillus sp. ASWW-2, was isolated from activated sludge, and its sulfur oxidation activity was characterized.Thiobacillus sp. ASWW-2 could oxidize elemental sulfur on the broad range from pH 2 to 8. When 5–50 g/L of elemental sulfur was supplemented as a substrate, the growth and sulfur oxidation activity ofThiobacillus sp. ASWW-2 was not inhibited. The specific sulfur oxidation rate of strain ASWW-2 decreased gradually until sulfate was accumulated in medium up to 10 g/L. In the range of sulfate concentration from 10 g/L to 50 g/L, the sulfur oxidation rate could keep over 2.0 g-S/g-DCW-d. It indicated thatThiobacillus sp. ASWW-2 has tolerance to high concentration of sulfate.     

Biological sulfide oxidation using autotrophic Thiobacillus sp.: evaluation of different immobilization methods and bioreactors

Aims:  Evaluation of various immobilization methods and bioreactors for sulfide oxidation using Thiobacillus sp. was studied.
Methods and Results:  Ca-alginate, K-carrageenan and agar gel matrices (entrapment) and polyurethane foam and granular activated carbon (adsorption) efficacy was tested for the sulfide oxidation and biomass leakage using immobilized Thiobacillus sp. Maximum sulfide oxidation of 96% was achieved with alginate matrix followed by K-carrageenan (88%). Different parameters viz. alginate concentration (1%, 2%, 3%, 4% and 5%), CaCl₂ concentration (1%, 2%, 3%, 4% and 5%), bead diameter (1, 2, 3, 4 and 5 mm), and curing time (1, 3, 6, 12 and 18 h) were studied for optimal immobilization conditions. Repeated batch experiments were carried out to test reusability of Ca-alginate immobilized beads for sulfide oxidation in stirred tank reactor and fluidized bed reactor (FBR) at different sulfide concentrations.
Conclusions:  The results proved to be promising for sulfide oxidation using Ca-alginate gel matrix immobilized Thiobacillus sp. for better sulfide oxidation with less biomass leakage.
Significance and Impact of the Study:  Biological sulfide oxidation is gaining more importance because of its simple operation. Present investigations will help in successful design and operation of pilot and industrial level FBR for sulfide oxidation.     

Sulfide oxidation in the phototrophic sulfur bacterium Chromatium vinosum

Sulfide oxidation in the phototrophic purple sulfur bacterium Chromatium vinosum D (DSMZ 180^T) was studied by insertional inactivation of the fccAB genes, which encode flavocytochrome c, a protein that exhibits sulfide dehydrogenase activity in vitro. Flavocytochrome c is located in the periplasmic space as shown by a PhoA fusion to the signal peptide of the hemoprotein subunit. The genotype of the flavocytochrome-c-deficient Chr. vinosum strain FD1 was verified by Southern hybridization and PCR, and the absence of flavocytochrome c in the mutant was proven at the protein level. The oxidation of thiosulfate and intracellular sulfur by the flavocytochrome-c-deficient mutant was comparable to that of the wild-type. Disruption of the fccAB genes did not have any significant effect on the sulfide-oxidizing ability of the cells, showing that flavocytochrome c is not essential for oxidation of sulfide to intracellular sulfur and indicating the presence of a distinct sulfide-oxidizing system. In accordance with these results, Chr. vinosum extracts catalyzed electron transfer from sulfide to externally added duroquinone, indicating the presence of the enzyme sulfide:quinone oxidoreductase (EC 1.8.5.-). Further investigations showed that the sulfide:quinone oxidoreductase activity was sensitive to heat and to quinone analogue inhibitors. The enzyme is strictly membrane-bound and is constitutively expressed. The presence of sulfide:quinone oxidoreductase points to a connection of sulfide oxidation to the membrane electron transport system at the level of the quinone pool in Chr. vinosum. Received: 5 November 1997 / Accepted: 30 March 1998     

Elemental sulfur as an intermediate of sulfide oxidation with oxygen byDesulfobulbus propionicus

The sulfate-reducing bacteriumDesulfobulbus propionicus oxidized sulfide, elemental sulfur, and sulfite to sulfate with oxygen as electron acceptor. Thiosulfate was reduced and disproportionated exclusively under anoxic conditions. When small pulses of oxygen were added to washed cells in sulfide-containing assays, up to 3 sulfide molecules per O₂ disappeared transiently. After complete oxygen consumption, part of the sulfide reappeared. The intermediate formed was identified as elemental sulfur by chemical analysis and turbidity measurements. When excess sulfide was present, sulfur dissolved as polysulfide. This process was faster in the presence of cells than in their absence. The formation of sulfide after complete oxygen consumption was due to a disproportionation of elemental sulfur (or polysulfide) to sulfide and sulfate. The uncoupler tetrachlorosalicylanilide (TCS) and the electron transport inhibitor myxothiazol inhibited sulfide oxidation to sulfate and caused accumulation of sulfur. In the presence of the electron transport inhibitor 2-n-heptyl-4-hydroxyquinoline-N-oxide (HQNO), sulfite and thiosulfate were formed. During sulfur oxidation at low oxygen concentrations, intermediary formation of sulfide was observed, indicating disproportionation of sulfur also under these conditions. It is concluded that sulfide oxidation inD. propionicus proceeds via oxidation to elemental sulfur, followed by sulfur disproportionation to sulfide and sulfate. Dedicated to Prof. Dr. Dr. h.c. Norbert Pfennig on the occasion of his 70th birthday     

Isotope effects associated with the anaerobic oxidation of sulfide by the purple photosynthetic bacterium, Chromatium vinosum

Abstract Small inverse isotope effects of 1–3‰ were consistently observed for the oxidation of sulfide to elemental sulfur during anaerobic photometabolism by Chromatium vinosum . The inverse fractionation can be accounted for by an equilibrium isotope effect between H₂S and HS⁻, and may indicate that C. vinosum (and other photosynthetic bacteria) utilizes H₂S rather than HS⁻ as the substrate during sulfide oxidation.     

Convenient method to prepare neutral sulfide solution for cultivation of phototrophic sulfur bacteria

A device is described for the preparation and storage of sterile neutral sulfide solution which is required for the repeated addition of this substrate to growing cultures of phototrophic sulfur bacteria.     

Nitrate promotes biological oxidation of sulfide in wastewaters: experiment at plant-scale

Biogenic production of sulfide in wastewater treatment plants involves odors, toxicity and corrosion problems. The production of sulfide is a consequence of bacterial activity, mainly sulfate-reducing bacteria (SRB). To prevent this production, the efficiency of nitrate addition to wastewater was tested at plant-scale by dosing concentrated calcium nitrate (Nutriox) in the works inlet. Nutriox dosing resulted in a sharp decrease of sulfide, both in the air and in the bulk water, reaching maximum decreases of 98.7% and 94.7%, respectively. Quantitative molecular microbiology techniques indicated that the involved mechanism is the development of the nitrate-reducing, sulfide-oxidizing bacterium Thiomicrospira denitrificans instead of the direct inhibition of the SRB community. Denitrification rate in primary sedimentation tanks was enhanced by nitrate, being this almost completely consumed. No significant increase of inorganic nitrogen was found in the discharged effluent, thus reducing potential environmental hazards to receiving waters. This study demonstrates the effectiveness of nitrate addition in controlling sulfide generation at plant-scale, provides the mechanism and supports the environmental adequacy of this strategy.     

硫氧化细菌的种类及硫氧化途径的研究进展

硫,作为生物必需的大量营养元素之一,参与了细胞的能量代谢与蛋白质、维生素和抗生素等物质代谢。自然界中,硫以多种化学形态存在,包括单质硫、还原性硫化物、硫酸盐和含硫有机物。硫氧化是硫元素生物地球化学循环的重要组成部分,通常是指单质硫或还原性硫化物被微生物氧化的过程。硫氧化细菌种类繁多,其硫氧化相关基因、酶和途径也多种多样。近几年,相关方面的研究已取得很多进展,但在不同层面仍存在一些尚未解决的科学问题。本文主要围绕硫氧化细菌的种类及硫氧化途径的研究进展进行了综述。