摘要：
Bovine liver cytochrome b
5 (cyt b
5), with heme bound noncovalently, has been converted into a cyt c-like protein (cyt b
5 N57C) by constructing a thioether linkage between the heme and the engineered cysteine residue. With no X-ray or NMR structure available, we herein performed a molecular modeling study of cyt b
5 N57C. On the other hand, using amino acid sequence information for a newly discovered member of the cyt b
5 family, domestic silkworm cyt b
5 (DS cyt b
5), we predicted the protein structure by homology modeling in combination with MD simulation. The modeling structure shows that both Cys57 in cyt b
5 N57C, and Cys56, a naturally occurring cysteine in DS cyt b
5, have suitable orientations to form a thioether bond with the heme 4-vinyl group, as the heme is in orientation A. In addition to providing structural information that was not previously obtained experimentally, these modeling studies provide insight into the formation of cyt c-like thioether linkages in cytochromes, and suggest that c-type cyt b
5 maturation involves a b-type intermediate.
作者机构：
[Dai, Yongming] Third People Hosp, Clin Lab, Kunshan City 215300, Jiangsu, Peoples R China.;[He, Fei] Shanghai Ctr Bioinformat Technol SCBIT, Shanghai 200235, Peoples R China.;Univ S China, Canc Res Inst, Sch Med, Hengyang City 421001, Hunan, Peoples R China.;[Wu, Yimou] Univ S China, Pathogen Biol Inst, Hengyang 421001, Peoples R China.
通讯机构：
[Runliang Gan] C;[Yimou Wu] P;Cancer Research Institute, University of South China, People’s Republic of China<&wdkj&>Cancer Research Institute, University of South China, School of Medicine, Hengyang City, People’s Republic of China<&wdkj&>Pathogenic Biology Institute, University of South China, People’s Republic of China<&wdkj&>Pathogenic Biology Institute, University of South China, Hengyang, China
关键词：
Epstein-Barr virus (EBV);Lymphocyte transformation;Lymphoblastoid cell line (LCL);Gene expression;Gene chip
摘要：
Epstain-Barr virus (EBV) can transform human B lymphocytes making them immortalized and inducing tumorigenic ability in vitro, but the molecular mechanisms remain unclear. The aim of the present study is to detect and analyze differentially expressed genes in two types of host cells, normal human lymphocytes and coupled EBV-transformed lymphoblasts in vitro using gene chips, and to screen the key regulatory genes of lymphocyte transformation induced by EB virus. Fresh peripheral blood samples from seven healthy donors were collected. EBV was used to transform lymphocytes in vitro. Total RNA was extracted from 7 cases of the normal lymphocytes and transformed lymphoblasts respectively, marked with dihydroxyfluorane after reverse transcription, then hybridized with 4 × 44 K Agilent human whole genome microarray. LIMMA, String, Cytoscape and other softwares were used to screen and analyze differentially expressed genes. Real-time PCR was applied to verify the result of gene expression microarrays. There were 1745 differentially expressed genes that had been screened, including 917 up-regulated genes and 828 down-regulated genes. According to the results of Generank, String and Cytoscape analyses, 38 genes may be key controlled genes related to EBV-transformed lymphocytes, including 22 up-regulated genes(PLK1, E2F1, AURKB, CDK2, PLCG2, CD80, PIK3R3, CDC20, CDC6, AURKA, CENPA, BUB1B, NUP37, MAD2L1, BIRC5, CDC25A, CCNB1, RPA3, HJURP, KIF2C, CDK1, CDCA8) and 16 down-regulated genes(FYN, CD3D, CD4, CD3G, ZAP70, FOS, HCK, CD247, PRKCQ, ITK, LCP2, CXCL1, CD8A, ITGB5, VAV3, CXCR4), which primarily control biological processes such as cell cycle, mitosis, cytokine-cytokine pathway, immunity response and so on. Human lymphocyte transformation induced by EB virus is a complicated process, involving multiple-genes and –pathways in virus-host interactions. Global gene expression profile analysis showed that EBV may transform human B lymphocytes by promoting cell cycle and mitosis, inhibiting cell apoptosis, hindering host immune function and secretion of cytokines.
摘要：
A novel method for determination of trace amounts of microorganism populations in solution was developed by using a multiwalled carbon nanotube (MWNT) modified glassy carbon electrode and square wave voltammetry (SWV). The simultaneous combination of MWNT and SWV allowed the electrochemical signal of electro-active materials in Escherichia coli O157:H7 (E. coli) to be dramatically amplified. Compared with a bare glassy carbon electrode, the MWNT-modified glassy carbon electrode showed catalytic properties in the oxidation of electro-active materials on cell surfaces. Moreover, SWV was proved to be more sensitive than cyclic voltammetry (CV) for investigation of the electrochemical behavior of cells. In this paper, a linear relationship was obtained between the SWV peak current and the cell concentration in the range 2 × 102–2 × 108 cell mL−1 with a detection limit of 2 × 102 cell mL−1. The effect of antibiotic drug Gentamycin Sulfate injection (GSI) on the growth of E. coli was also investigated.
作者机构：
[Lu, Chunxue; Li, Zhihong; Peng, Bo; Zeng, Hao; Zhong, Guangming] Univ Texas Hlth Sci Ctr San Antonio, Dept Microbiol & Immunol, San Antonio, TX 78229 USA.;[Zhou, Zhiguan; Li, Zhihong] Cent S Univ, Xiangya Hosp 2, Dept Surg, Changsha, Hunan, Peoples R China.;[Lu, Chunxue; Wu, Yimou; Peng, Bo] Univ S China, Dept Pathol & Microbiol, Hengyang, Hunan, Peoples R China.
通讯机构：
[Li, Zhihong] U;Univ Texas Hlth Sci Ctr San Antonio, Dept Microbiol & Immunol, San Antonio, TX 78229 USA.
关键词：
Chlamydia infection;Chlamydia trachomatis;Antibodies;Enzyme-linked immunoassays;Chlamydia;Mouse models;Animal models of infection;Glycogens
摘要：
We evaluated 7 C. muridarum ORFs for their ability to induce protection against chlamydial infection in a mouse intravaginal infection model. These antigens, although encoded in C. muridarum genome, are transcriptionally regulated by a cryptic plasmid that is known to contribute to C. muridarum pathogenesis. Of the 7 plasmid-regulated ORFs, the chlamydial glycogen phosphorylase or GlgP, when delivered into mice intramuscularly, induced the most pronounced protective immunity against C. muridarum intravaginal infection. The GlgP-immunized mice displayed a significant reduction in vaginal shedding of live organisms on day 14 after infection. The protection correlated well with a robust C. muridarum-specific antibody and a Th1-dominant T cell responses, which significantly reduced the severity but not overall incidence of hydrosalpinx. The GlgP-induced partial protection against upper genital tract pathology suggests that GlgP may be considered a component for a multi-subunit vaccine. These results have demonstrated that intramuscular immunization of mice with purified proteins can be used to identify vaccine antigens for preventing intravaginal infection with C. trachomatis in humans.
期刊：
CANADIAN JOURNAL OF MICROBIOLOGY,2012年58(7):898-908 ISSN：0008-4166
通讯作者：
Wu, Yimou
作者机构：
[Liu, Yan; Wu, Yimou; Liu, Liangzhuan; Zhu, Cuiming; You, Xiaoxing; Zeng, Yanhua] Univ S China, Inst Pathogen Biol, Hengyang 421001, Peoples R China.;[He, Jun] Univ S China, Affiliated Nanhua Hosp, Hengyang 421000, Peoples R China.
通讯机构：
[Wu, Yimou] U;Univ S China, Inst Pathogen Biol, Hengyang 421001, Peoples R China.
关键词：
phage display peptide library;mimic epitope;Mycoplasma genitalium;adhesion protein;banque d’exposition de peptides sur phage;mimes fonctionnels d’épitopes;Mycoplasma genitalium;protéine d’adhésion
摘要：
Mycoplasma genitalium adhesion protein (MgPa) is the major adhesion protein of M. genitalium, and its Cterminal domain (amino acid 1075-1444) is the most immunogenic region. However, the exact epitopes of the adhesion protein of M. genitalium are still unclear. We used the purified polyclonal antibody against the recombinant adhesion protein to screen the mimic epitopes of MgPa using a random 12-peptide phage display library. Immunoscreening via the phage display peptide library revealed that 3 motifs (P-S-A-A/V-X-R-F/W-E/S-L-S-P, A-K-I/L-T/Q-X-T-L-X-L, and K-S-L-S-R-X-DX- I) may represent 3 different mimotopes of MgPa. Results of bioinformatics analysis by MIMOX demonstrated that the key consensus amino acid residues in the aligned mimotopes may be S, A, and F for cluster 1; A, K, I, T, and L for cluster 2; and K, S, L, R, D, and I for cluster 3. Three representative phages could recognize sera from M. genitalium-positive patients to varying degrees, whereas they could not recognize the sera from Mycoplasma pneumoniae-positive patients or the sera from healthy people. These findings will help to clarify the mimic epitopes of MgPa to facilitate diagnosis of the antigen and to understand the antigenic structure of MgPa.
作者：
Li Chun;Wu Yimou;Zhu Cuiming;Zhong Lili;Lü Jianhua
作者机构：
[Li Chun; Wu Yimou; Zhu Cuiming] Pathogenic Biology Institute, School of medicine,University of South China, Hengyang 421001, China;[Zhong Lili] Pediatrics, Hunan Provincial People's Hospital,Changsha 410000, China;[Lü Jianhua] Pediatrics, The First Hospital of Nanhua University,Hengyang 421001, China
会议名称：
中华医学会第七次全国中青年检验医学学术会议
会议时间：
2012-5-3
会议地点：
南京
会议主办单位：
中华医学会
会议论文集名称：
中华医学会第七次全国中青年检验医学学术会议论文集
摘要：
<正>Background & objectives Mycoplasma pneumoniae is known to be a major cause of respiratory tract infections and pneumonia in children.Macrolides are generally considered as the treatment of choice in children.A specific diagnosis is important to institute the appropriate treatment.The aim of this study was to detect mycoplasma pneumoniae from clinical samples
作者机构：
[Lu, Chunxue; Peng, Bo; Gong, Siqi; Zhong, Guangming] Univ Texas Hlth Sci Ctr San Antonio, Dept Microbiol & Immunol, San Antonio, TX 78229 USA.;[Lu, Chunxue; Wu, Yimou; Peng, Bo; Zhong, Guangming] Univ S China, Dept Microbiol, Hengyang, Hunan, Peoples R China.;[Bailey, Robin L.; Mabey, David W.; Holland, Martin J.] London Sch Hyg & Trop Med, Dept Clin Res, London WC1E 7HT, England.;[Holland, Martin J.] MRC Labs, Banjul, Gambia.;[Zhong, Guangming] Univ Texas Hlth Sci Ctr San Antonio, Dept Microbiol & Immunol, 7703 Floyd Curl Dr, San Antonio, TX 78229 USA.
通讯机构：
[Zhong, Guangming] U;Univ Texas Hlth Sci Ctr San Antonio, Dept Microbiol & Immunol, 7703 Floyd Curl Dr, San Antonio, TX 78229 USA.
摘要：
PURPOSE. Chlamydia trachomatis is the leading infectious cause of blindness. The goal of the current study was to search for biomarkers associated with C. trachomatis-induced ocular pathologies. METHODS. We used a whole genome scale proteome array to systematically profile antigen specificities of antibody responses to C. trachomatis infection in individuals from trachoma-endemic communities with or without end-stage trachoma (trichiasis) in The Gambia. RESULTS. When 61 trichiasis patients were compared with their control counterparts for overall antibody reactivity with organisms of different chlamydial species, no statistically significant difference was found. Both groups developed significantly higher titers of antibodies against C. trachomatis ocular serovars A and B than ocular serovar C, genital serovar D, or Chlamydia psittaci, whereas the titers of anti-Chlamydia pneumoniae antibodies were the highest. When antisera from 33 trichiasis and 26 control patients (with relatively high titers of antibodies to C. trachomatis ocular serovars) were reacted with 908 C. trachomatis proteins, 447 antigens were recognized by at least 1 of the 59 antisera, and 10 antigens by 50% or more antisera, the latter being designated as immunodominant antigens. More importantly, four antigens were preferentially recognized by the trichiasis group, with antigens CT414, CT667, and CT706 collectively reacting with 30% of trichiasis antisera but none from the normal group, and antigen CT695 reacting with 61% of trichiasis but only 31% of normal antisera. On the other hand, eight antigens were preferentially recognized by the control group, with antigens CT019, CT117, CT301, CT553, CT556, CT571, and CT709 together reacting with 46% of normal antisera and none from the trichiasis group, whereas antigen CT442 reacted with 35% of normal and 19% of trichiasis antisera respectively. CONCLUSIONS. The current study, by mapping immunodominant C. trachomatis antigens and identifying antigens associated with both ocular pathology and protection, has provided important information for further understanding chlamydial pathogenesis and the development of subunit vaccines. (Invest Ophthalmol Vis Sci. 2012;53:2551-2559) DOI:10.1167/iovs.11-9212
摘要：
The biological toxicity of uranyl ion (UO
2
2+
) lies in interacting with proteins and disrupting their native functions. The structural and functional consequences of UO
2
2+
interacting with cytochrome b
5 (cyt b
5), a small membrane heme protein, and its heme axial ligand His39Ser variant, cyt b
5 H39S, were investigated both experimentally and theoretically. In experiments, although cyt b
5 was only slightly affected, UO
2
2+
binding to cyt b
5 H39S with a K
D of 2.5 μM resulted in obvious alteration of the heme active site, and led to a decrease in peroxidase activity. Theoretically, molecular simulation proposed a uranyl ion binding site for cyt b
5 at surface residues of Glu37 and Glu43, revealing both coordination and hydrogen bonding interactions. The information gained in this study provides insights into the mechanism of uranyl toxicity toward membrane protein at an atomic level.
作者机构：
[Wu YiMou; Zhou Zhou; Su ShengMei; Chen ChaoQun; Li ZhongYu] Univ S China, Sch Med, Dept Microbiol & Immunol, Hengyang 421001, Peoples R China.;[Huang QiuLin] Univ S China, Affiliated Hosp 1, Dept Gen Surg, Hengyang 421001, Peoples R China.;[Zhong GuangMing] Univ Texas Hlth Sci Ctr San Antonio, Dept Microbiol & Immunol, San Antonio, TX 78229 USA.
通讯机构：
[Wu YiMou] U;Univ S China, Sch Med, Dept Microbiol & Immunol, Hengyang 421001, Peoples R China.
关键词：
Chlamydia trachomatis;CT440;inclusion membrane protein
摘要：
The inclusion membrane proteins play potentially important roles in chlamydial biology and pathogenesis. Here we localized and characterized the hypothetical protein CT440 in Chlamydia trachomatis-infected cells. The open reading frame (ORF) encoding the CT440 protein from the C. trachomatis serovar D genome was cloned into the prokaryotic expression vector pGEX-6p and expressed as a glutathione-S-transferase (GST) fusion protein in E. coli XL1-Blue. The CT440 fusion protein was used to immunize mice to raise antigen-specific antibody. After verification by Western blot and immunofluorescence assay (IFA), the specific antibody was used to localize the endogenous CT440 protein and to detect its expression pattern in Chlamydia-infected cells. Cytosolic expression of CT440 in HeLa cells was also carried out to evaluate the effect of the CT440 protein on the subsequent chlamydial infection. The results showed that the hypothetical protein CT440 was localized in the C. trachomatis inclusion membrane, and was detectable 12 h after chlamydial infection. Expression of CT440 in the cytoplasm did not inhibit the subsequent chlamydial infection. In summary, we have identified a new inclusion membrane protein that may be an important candidate for understanding C. trachomatis pathogenesis.
