化学学报 ›› 2015, Vol. 73 ›› Issue (4): 337-342.DOI: 10.6023/A15010015 上一篇    下一篇

研究论文

具核梭杆菌具核亚种蛋白质组及其在癌症pH环境下的差异蛋白质组分析

殷薛飞a,b, 刘晓慧a,b, 申华莉a,b, 金红a,b, 杨芃原a,b   

  1. a 复旦大学化学系 上海 200433;
    b 复旦大学生物医学研究院 上海 200032
  • 收稿日期:2015-01-06 出版日期:2015-04-14 发布日期:2015-01-29
  • 通讯作者: 申华莉, 金红 E-mail:jinhong@fudan.edu.cn;shenghuali@fudan.edu.cn
  • 基金资助:

    项目受863计划(No. 2012AA020201), 国家"211工程"项目高等学校仪器设备和优质资源共享系统(cers-1-66), 高等学校博士学科点专项科研基金(No. 20130071140007)资助.

Whole Proteome of Fusobacterium nucleatum and Quantitative Analysis of Proteomic Change in Cancer Environment

Yin Xuefeia,b, Liu Xiaohuia,b, Shen Hualia,b, Jin Honga,b, Yang Pengyuana,b   

  1. a Department of Chemistry, Fudan University, Shanghai 200433;
    b Institute of Biomedical Science, Fudan University, Shanghai 200032
  • Received:2015-01-06 Online:2015-04-14 Published:2015-01-29
  • Supported by:

    Project supported by MOST 863 Program (No. 2012AA020201) and CERS-1-66 (CERS-China Equipment and Education Resources System) and Research Fund for the Doctoral Program of Higher Education of China (No. 20130071140007).

利用LC-MS/MS对F. nucleatum的蛋白质表达谱进行了深入研究, 共鉴定到1198个蛋白质的表达, 占基因组58%的编码基因. 通过在pH 6.5(癌症组织pH环境)和pH 7.5(正常组织pH环境)两种条件下F. nucleatum蛋白质表达的定量蛋白质组学分析, 发现处于癌症微环境pH条件下蛋白质表达的变化明显集中于金属离子转运, 硫胺素代谢, 糖代谢等过程和功能. 产丁酸发酵的能量代谢通路中的七个代谢酶在蛋白质组数据中找到, 其中有五个在癌症pH条件下显著下调, 这五个酶包含了丁酸盐代谢的整个过程, 这为结直肠癌患者肠道丁酸盐含量降低提供了新的证明. 此外, 癌症pH条件下F. nucleatum的丁酸代谢受到抑制, 造成产丁酸能力下降, 可能是其促进结直肠癌发展在代谢水平上的原因之一.

关键词: 具核梭杆菌, 蛋白质组, 非标定量, pH 环境, 丁酸代谢

In this paper, we systematically analyzed the proteome of F. nucleatum by using liquid chromatography coupled tandem mass spectrometry (LC-MS/MS) and label free quantification in different culturing pH conditions. We identified over 950 proteins in each LC-MS/MS run. Totally 1198 proteins were identified in two different pH conditions, which correspond to 58% of the protein coding genes among the whole genome of F. nucleatum. The three replicates of pH 6.5 (pH condition of cancer tissue) and pH 7.5 (pH condition of normal tissue) coincide for more than 70% of all the identified peptides and more than 90% of the identified proteins, which indicates the stability and reproducibility of the experiments. By label-free quantitative analysis of the proteome, 1001 proteins have quantitative information. We found that 263 proteins were shown significant expression changed between pH 6.5 and pH 7.5. According to the gene ontology analysis, the significant expression changed proteins were focused on several metabolism processes and functions, such as metal ions transport, thiamin metabolic and carbohydrate metabolism and so on. Butyric acid fermentation is one of the important metabolism pathway in F. nucleatum which also have relationship with colorectal cancer. Butyric acid fermentation pathway including five categories of metabolic enzymes which contains eight protein coding genes. We have found five metabolic enzyme (acetyl-CoA acetyltransferase, 3-hydroxybutyryl-CoA dehydrogenase, crotonase, butyryl-CoA dehydrogenase and acetoacetate:butyrate/acetate CoA transferase) significant down regulation in pH condition of cancer tissue. Therefore, the butyric acid fermentation pathway were inhibited in F. nucleatum when it is living in colorectal cancer micro-environment. As the decrease of the butyric acid production is one of the phenomenon in colorectal cancer patient and F. nucleatum could promote colorectal cancer development, we verified F. nucleatum have contribution to this phenomenon. And the inhibition of butyric acid fermentation may give evidence that F. nucleatum could promote the colorectal cancer development in metabolism level.

Key words: Fusobacterium nucleatum, proteome, label free quantification, pH condition, butyric acid fermentation