title: A novel multidomain polyketide synthase is essential for zeamine production and the virulence of Dickeya zeae.
abstract: Dickeya zeae is the causal agent of the rice foot rot disease, but its mechanism of infection remains largely unknown. In this study, we identified and characterized a novel gene designated as zmsA. The gene encodes a large protein of 2,346 amino acids in length, which consists of multidomains arranged in the order of N-terminus, β-ketoacyl synthase, acyl transferase, acyl carrier protein, β-ketoacyl reductase, dehydratase. This multidomain structure and sequence alignment analysis suggest that ZmsA is a member of the polyketide synthase family. Mutation of zmsA abolished antimicrobial activity and attenuated the virulence of D. zeae. To determine the relationship between antimicrobial activity and virulence, active compounds were purified from D. zeae EC1 and were structurally characterized. This led to identification of two polyamino compounds, i.e., zeamine and zeamine II, that were phytotoxins and potent antibiotics. These results have established the essential role of ZmsA in zeamine biosynthesis and presented a new insight on the molecular mechanisms of D. zeae pathogenicity.
authors: Department of plant Pathology, South China Agricultural University, Guangzhou 51642, People's Republich of China.
authors: Jianuan
authors: J
authors: Zhou
authors: Haibao
authors: H
authors: Zhang
authors: Jien
authors: J
authors: Wu
authors: Qiongguang
authors: Q
authors: Liu
authors: Pinggen
authors: P
authors: Xi
authors: Jasmine
authors: J
authors: Lee
authors: Jinling
authors: J
authors: Liao
authors: Zide
authors: Z
authors: Jiang
authors: Lian-Hui
authors: LH
authors: Zhang
mesh_terms: D000429:Alcohol Oxidoreductases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001427:Bacterial Toxins / Q000096:biosynthesis / Q000235:genetics / Q000633:toxicity; D001483:Base Sequence; D001937:Brassica / Q000382:microbiology; D002874:Chromosome Mapping; D004269:DNA, Bacterial / Q000235:genetics; D004755:Enterobacteriaceae / Q000201:enzymology* / Q000235:genetics / Q000472:pathogenicity*; D005798:Genes, Bacterial; D005816:Genetic Complementation Test; D018525:Germination / Q000187:drug effects; D054884:Host-Pathogen Interactions / Q000235:genetics / Q000502:physiology; D018942:Macrolides / Q000378:metabolism*; D008969:Molecular Sequence Data; D009154:Mutation; D012275:Oryza / Q000187:drug effects / Q000254:growth & development / Q000382:microbiology*; D010935:Plant Diseases / Q000382:microbiology; D011073:Polyamines / Q000378:metabolism*; D011198:Solanum tuberosum / Q000382:microbiology; D014774:Virulence / Q000235:genetics / Q000502:physiology
chemical_list: D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004269:DNA, Bacterial; D018942:Macrolides; D011073:Polyamines; C547236:zeamine; D000429:Alcohol Oxidoreductases; C087192:polyketide synthase ketoreductase