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Chinese Physics Letters 2003年第12期20卷 2148-2151页

作者：刘伟民朱荣毅夏辰安刘源徐春和钱士雄 DepartmentofPhysics FudanUniversityShanghai200433 NationalKeyLaboratoryofSurfaceScience FudanUniversityShanghai200433 ShanghaiInstituteofPlantPhysiologyandEcology ShanghaiInstituteforBiologicalSciencesChineseAcademyofSciencesShanghai200032

Two kinds of antenna complexes LH2 of rhodobacter sphaeroides, wild type RS601 and the removal of B800 pigments (B800-released), were used in our experiment. These two LH2 complexes show quite different behaviour in absorption and femtosecond dynamics. By using the femtosecond pump–probe technique, the energy transfer processes occurring in two complexes were studied. Because of removing the B800 pigment from the LH2 in B800-released LH2 complex, the energy transfer between the B800 to B850 pigment was completely eliminated, while the pure internal energy transfer within the exciton states of B850 pigment could be carefully investigated. The results show that, at B800 absorption band, B800-released LH2 obviously shows a dominated transient absorption different from the photobleaching observed in RS601; while at the B850 band, these two complexes show similar photobleaching behaviour.

关键词： rhodobacter sphaeroides PLOD2 gene Exciton complexes energy exchange Energy transfer absorption Pigment rhodobacter Femtosecond Photobleaching

Impacts of Fe2+on 5-aminolevulinic acid(ALA)biosynthesis of rhodobacter sphaeroides in wastewater treatment by regulating nif gene expression

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Journal of Environmental Sciences 2018年第8期30卷 11-19页

作者： Shuli Liu Zhihong Zheng Jingxi Tie Jia Kang Guangming Zhang Jie Zhang School of Environmental and Municipal Engineering North China University of Water Resources and Electric PowerZhengzhou 450000China Henan Key Laboratory of Water Environment Simulation and Treatment Zhengzhou 450046China Henan Engineering Research Center of Water Pollution and Soil Damage Remediation Zhengzhou 450046China School of Environment and Resource Renmin University of ChinaBeijing 100872China School of Municipal and Environmental Engineering Harbin Institute of TechnologyHarbin 150090China

This study aimed to increase bacterial growth and 5-aminolevulinic acid（ALA） biosynthesis of rhodobacter sphaeroides in wastewater treatment through adding ferrous ion（ Fe2＋）. Results demonstrated that Fe2＋ effectively enhanced the biomass production and ALA yield of R. sphaeroides. Moreover, the optimal Fe2＋ dosage was found to be 400 μmol/L, which was associated with the highest biomass of 4015.3 mg/L and maximum ALA yield of 15.9 mg/g-dry cell weight（mg/g-DCW）. Mechanism analysis revealed that Fe2＋ vastly improved Adenosine Triphosphate（ATP） production by up-regulating the nif gene expression, and increasing ATP enhanced the biomass and ALA yield by supplying energy for bacterial growth and ALA biosynthesis, respectively. Correlation analysis showed that the ALA and ATP yields had positive relation with nifA and nifU gene expression. In addition, the nifA and nifU gene expression displayed high consistency of co-transcription at the optimal Fe2＋ dosage.

关键词： Ferrous ion 5-Aminolevulinic acid rhodobacter sphaeroides ATP production nif genes Up-regulation

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Screening and engineering of high-activity promoter elements through transcriptomics and red fluorescent protein visualization in rhodobacter sphaeroides

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Synthetic and Systems Biotechnology 2021年第4期6卷 335-342页

作者： Tong Shi Lu Zhang Mindong Liang Weishan Wang Kefeng Wang Yue Jiang Jing Liu Xinwei He Zhiheng Yang Haihong Chen Chuan Li Dongyuan Lv Liming Zhou Biqin Chen Dan Li Li-Xin Zhang Gao-Yi Tan State Key Laboratory of Bioreactor Engineering(SKLBE) And School of BiotechnologyEast China University of Science and Technology(ECUST)Shanghai200237China State Key Laboratory of Microbial Resources and CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of Sciences(CAS)Beijing100101China Inner Mongolia Kingdomway Pharmaceutical Co. LtdHohhot010206China

The versatile photosyntheticα-proteobacterium rhodobacter sphaeroides,has recently been extensively engineered as a novel microbial cell factory(MCF)to produce pharmaceuticals,nutraceuticals,commodity chemicals and even ***,there are no well-characterized high-activity promoters to modulate gene transcription during the engineering of *** this study,several native promoters from *** JDW-710(JDW-710),an industrial strain producing high levels of co-enzyme Q10(Q10)were selected on the basis of transcriptomic *** candidate promoters were then characterized by using gusA as a reporter *** native promoters,Prsp_7571 and Prsp_6124,showed 620%and 800%higher activity,respectively,than the tac promoter,which has previously been used for gene overexpression in *** addition,a Prsp_7571-derived synthetic promoter library with strengths ranging from 54%to 3200%of that of the tac promoter,was created on the basis of visualization of red fluorescent protein(RFP)expression in ***,as a demonstration,the synthetic pathway of Q10 was modulated by the selected promoter T334*in JDW-710;the Q10 yield in shake-flasks increased 28%and the production reached 226 mg/*** well-characterized promoters should be highly useful in current synthetic biology platforms for refactoring the biosynthetic pathway in ***-derived MCFs.

关键词： rhodobacter sphaeroides Promoter library Transcriptomics Co-enzyme Q_(10) Red fluorescent protein

Bioproduction of D-psicose using permeabilized cells of newly isolated rhodobacter sphaeroides SK011

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Frontiers of Chemical Science and Engineering 2009年第4期3卷 393-398页

作者： Longtao ZHANG Bo JIANG Wanmeng MU Tao ZHANG State Key Laboratory of Food Science and Technology Jiangnan UniversityWuxi 214122China Institute of Animal Husbandry and Veterinary Medicine Fujian Academy of Agricultural SciencesFuzhou 350013China

D-psicose exits in an extremely small amount in nature and is difficult to be chemically *** three bacteria have been used in the biotransformation of D-psicose from *** this paper,another bacterium which could convert D-fructose to D-psicose was isolated and identified as rhodobacter *** process parameters of D-psicose production using permeabilized cells of rhodobacter sphaeroides SK011 were optimized,including the permeabilization procedure:0.1%(w/v)CTAB,10 min,and reaction conditions:cell concentration,30 g dry cell wt/L;concentration of substrate,50 g/L;40℃,pH 9.0;reaction time,8 *** the optimized conditions,the permeabilized cells produced approximately 6.5 g/L D-psicose with a Dpsicose productivity of 0.82 g·L^(-1)·h^(-1).This is the first report of bioproduction of D-psicose using permeabilized cells of rhodobacter sphaeroides.

关键词： bioproduction D-psicose permeabilized cells rhodobacter sphaeroides

Isolation,Identification of Bacillus Thuringiensis/Cereus and Its Enhancement on Protein Wastewater Treatment by rhodobacter sphaeroides

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Journal of Harbin Institute of Technology(New Series) 2016年第5期23卷 69-75页

作者： Shuli Liu Guangming Zhang Jie Zhang School of Environmental and Municipal Engineering North China University of Water Resources and Electric Power School of Municipal and Environmental Engineering Harbin Institute of Technology School of Environment and Resource Renmin University of China

In order to enhance the degrading protein capability of purple non-sulfur bacteria(PNSB),an effective strain,L2,was used to co-culture with rhodobacter sphaeroides *** effects of added strain on protein removal of *** were *** showed that strain L2,being identified as Bacillus thuringiensis/cereus,had a high potential for producing protease with a production of 295 U/m *** optimal ***/cereus(40 μL) could significantly increase protein degradation of *** removal and biomass production were improved by 483% and 67%,***/total biomass production was more than 95%.Theoretical analysis revealed that *** syntrophically interacted with ***/*** degradation of ***/cereus provided small molecule substrates(VFAs) for *** growth and cells materials synthesis.

关键词： rhodobacter sphaeroides protein degradation protease Bacillus thuringiensis / cereus

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浑球红细菌 (rhodobacter sphaeroides)中氢化酶正调节基因hupR的克隆及功能分析(英文)

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生物化学与生物物理学报 2001年第6期33卷 607-614页

作者：徐冬青吴永强中国科学院上海生命科学研究院植物生理生态研究所中国科学院上海生命科学研究院植物生理生态研究所上海200032

从光合细菌rhodobactersphaeroides基因文库中分离出含有氢化酶基因簇 (hup)的粘粒cosmid 1后 ,亚克隆了R .sphaeroides的氢化酶调节基因hupR ,测定了hupR的核苷酸序列 ,并完成了氢化酶基因簇的部分物理图谱。实验结果表明 ,hupR基因全... 详细信息

从光合细菌rhodobactersphaeroides基因文库中分离出含有氢化酶基因簇 (hup)的粘粒cosmid 1后 ,亚克隆了R .sphaeroides的氢化酶调节基因hupR ,测定了hupR的核苷酸序列 ,并完成了氢化酶基因簇的部分物理图谱。实验结果表明 ,hupR基因全长 1476bp ,编码的HupR蛋白分子量约为 5 4.0 31kD (EMBL接受号 :AJ2 43734 )。与R .capsulatus中HupR相比 ,同源性高达 73%。同源性比较结果表明 ,它属于双组分调节系统中受体蛋白。hupR基因在E .coli中进行了体外表达 ,纯化后测定得到的HupR蛋白的分子量大小与hupR基因推测的分子量大小一致。通过双交换 ,将卡那霉素抗性基因插入hupR基因 ,获得丧失氢化酶活性的hupR-的突变株 ,KR5和KR7。hupS∷lacZ融合基因在野生型中的转录表达量是在该突变株中的 7～ 9倍。将hupR基因置于弱启动子 pfru下游 ,构建了质粒pNRC3,并将其导入hupR-的突变株 ,可使突变株重新获得氢化酶活性。以上结果说明 ,HupR蛋白对氢化酶的转录表达起着正调节作用。在HupR蛋白的磷酸化区域进行定点和缺失突变 ,不影响HupR激活氢化酶基因的表达 ,推测HupR蛋白是在非磷酸化的状态下起调节作用的。

关键词： rhodobacter sphaeroides hup基因簇 hupR基因转录氢化酶

Quantum Chemical Studies on Proteins in the Reaction Center of rhodobacter sphaeroides

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Acta Botanica Sinica 2001年第6期43卷 565-570页

作者：徐红马淑华沈玲玲张晓东张兴康张启元中国科学院化学研究所分子科学中心分子动态与稳态国家重点实验室北京100080

The electronic structure of protein chains L and M in photosynthetic reaction center (PRC) of rhodobacter sphaeroides (Van Niel) Imhoff, Truper et Pfennig) was studied by using the Overlapping Dimer Approximation method and the Extended Negative Factor Counter method at ab initio level. The result indicated that: (1) Amino acid residues, the molecular orbitals of which composed the main components of frontier orbitals of protein chain L (M), are located at the random coil areas of chain L (alpha helix areas of chain M). Since the random coil is flexible and more easy to change its conformation in the electron transfer process and to reduce the energy of the system, and the structure of the alpha helix is reletively stable, this difference might be one of the causes for the electron transfer in photosynthetic reaction center (PRC) only takes place along the L branch. (2) The His residues which axially coordinated to the 'special pair' P and accessory chlorophyll molecules (ABChls) are essentially important for the E-LUMO levels of P and ABChl. But, the corresponding molecular orbitals of these His residues do not appear in the composition of frontier orbitals of protein chains. It means that the interaction between pigment molecules and protein chains do not influence the contribution to the frontier orbitals of protein chains explicitly, but influences the corresponding E-LUMO levels significantly.

关键词： photosynthetic reaction center rhodobacter sphaeroides electronic structure of protein ab initio Extended Negative Factor Counter method (ENFC)

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Optimization of Coenzyme Q10Production Procedure from Genetic Engineered rhodobacter sphaeroides Overexpressing UbiG

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Agricultural Biotechnology 2020年第1期9卷 6-8页

作者： Zhiping ZHAO Xinning XU Ziyi YE Lili JI Jiamin ZHANG Wei WANG Meat Processing Key Laboratory of Sichuan Province Chengdu University

In the present study, single factors including fermentation temperature, inoculate amount, fermentation duration, and ratio of fermentation medium volume to total flask volume(dissolved oxygen tension) were optimized for enhancing the production of coenzyme Q10 from genetic engineered rhodobacter sphaeroides overexpressing UbiG. The experimental results suggested that optimal single factors were: inoculate amount 2%, fermentation temperature 30 ℃, fermentation duration 48 h, and ratio of fermentation medium volume to total flask volume 80%. The present study will promote the large scale production of CoQ10 from microorganisms.

关键词： CoQ 10 rhodobacter sphaeroides Genetic engineering Optimization Fermentation

One-Step Purification of Functional Light-harvesting 2 Complexes from rhodobacter sphaeroides

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One-Step Purification of Functional Light-harvesting 2 Compl...

Characterization and nitrite removal of photosynthetic bacteria,rhodobacter sphaeroides,isolated from shrimp sludge

重庆市生物化学与分子生物学学术会议

作者： Zhiping Zhao,Zongli Hu,Yan Liang,Tingzhang Hu,Yun Tu,Guoping Chen (Key Laboratory of Biorheological Science and Technology,Ministry of Education,Bioengineering College,Chongqing University,Chongqing 400044)

Most common method for isolation of light-harvesting 2 complexes(LH2) is very time-consuming. Functional LH2 complexes were rapidly purified from rhodobacter sphaeroides by one-step purification using affinity *** ext... 详细信息

关键词： LH2 His-tag spectral absorption rhodobacter sphaeroides

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Characterization and nitrite removal of photosynthetic bacte...