期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:2002
卷号:99
期号:26
页码:17037-17042
DOI:10.1073/pnas.252514899
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:The study of the metabolome presents numerous challenges, first among them being the cataloging of its constituents. A step in this direction will be the development of tools to identify metabolites that share common structural features. The importance of sulfated molecules in cell-cell communication motivated us to develop a rapid two-step method for identifying these metabolites in microorganisms, particularly in pathogenic mycobacteria. Sulfurcontaining molecules were initially identified by mass spectral analysis of cell extracts from bacteria labeled metabolically with a stable sulfur isotope (34SO[IMG]f1.gif" ALT="Formula" BORDER="0">). To differentiate sulfated from reduced-sulfur-containing molecules, we employed a mutant lacking the reductive branch of the sulfate assimilation pathway. In these sulfur auxotrophs, heavy sulfate is channeled exclusively into sulfated metabolites. The method was applied to the discovery of several new sulfated molecules in Mycobacterium tuberculosis and Mycobacterium smegmatis. Because a sulfur auxotrophic strain is the only requirement of the approach, many microorganisms can be studied in this manner. Such genetic engineering in combination with stable isotopic labeling can be applied to various metabolic pathways and their products.