title: Functional characterization and transcriptional analysis of icd2 gene encoding an isocitrate dehydrogenase of Xanthomonas campestris pv. campestris.
abstract: Isocitrate dehydrogenase (IDH) catalyzes the oxidative decarboxylation of isocitrate to alpha-ketoglutarate. In the genome of Xanthomonas campestris pv. campestris, the phytopathogen that causes black rot in cruciferous plants, two putative IDH genes, icd1 and icd2, have been annotated. Their physiological roles in X. campestris pv. campestris are unclear. In this study, the icd2 gene from X. campestris pv. campestris was characterized in detail. We demonstrated genetically that icd2 gene encodes a functional IDH, and is involved in virulence as well as bacterial attachment. Furthermore, the icd2 transcription initiation site was mapped at nucleotide G, 127 nucleotide upstream of the icd2 translation start codon. In addition, promoter analysis revealed that icd2 expression exhibits a distinct expression profile under different culture conditions, is subjected to catabolite repression, and is affected by acetate. This is the first time that the function and transcription of icd2 have been characterized in the crucifer pathogen X. campestris pv. campestris.
authors.affiliation: Department of Medical Laboratory Science and Biotechnology, Central Taiwan University of Science and Technology, Taichung, 406, Taiwan.
authors.forename: Ying-Chuan
authors.initials: YC
authors.lastname: Chiang
authors.affiliation: Department of Medical Laboratory Science and Biotechnology, Central Taiwan University of Science and Technology, Taichung, 406, Taiwan.
authors.forename: Chao-Tsai
authors.initials: CT
authors.lastname: Liao
authors.affiliation: Department of Medical Laboratory Science and Biotechnology, Central Taiwan University of Science and Technology, Taichung, 406, Taiwan.
authors.forename: Shin-Chiao
authors.initials: SC
authors.lastname: Du
authors.affiliation: Department of Medical Laboratory Science and Biotechnology, Central Taiwan University of Science and Technology, Taichung, 406, Taiwan. ymhsiao@ctust.edu.tw.
authors.forename: Yi-Min
authors.initials: YM
authors.lastname: Hsiao
mesh_terms: D001422:Bacterial Adhesion; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001937:Brassica / Q000382:microbiology; D015964:Gene Expression Regulation, Bacterial; D007521:Isocitrate Dehydrogenase / Q000235:genetics / Q000378:metabolism*; D007656:Ketoglutaric Acids / Q000378:metabolism; D010935:Plant Diseases / Q000382:microbiology; D011401:Promoter Regions, Genetic; D024363:Transcription Initiation Site; D014774:Virulence; D016959:Xanthomonas campestris / Q000201:enzymology* / Q000235:genetics / Q000472:pathogenicity / Q000502:physiology
chemical_list: D001426:Bacterial Proteins; D007656:Ketoglutaric Acids; D007521:Isocitrate Dehydrogenase
keywords: Attachment; Pathogenicity; Reporter assay