title: Proteomic analysis of Ketogulonicigenium vulgare under glutathione reveals high demand for thiamin transport and antioxidant protection.
abstract: Ketogulonicigenium vulgare, though grows poorly when mono-cultured, has been widely used in the industrial production of the precursor of vitamin C with the coculture of Bacillus megaterium. Various efforts have been made to clarify the synergic pattern of this artificial microbial community and to improve the growth and production ability of K. vulgare, but there is still no sound explanation. In previous research, we found that the addition of reduced glutathione into K. vulgare monoculture could significantly improve its growth and productivity. By performing SEM and TEM, we observed that after adding GSH into K. vulgare monoculture, cells became about 4-6 folds elongated, and formed intracytoplasmic membranes (ICM). To explore the molecular mechanism and provide insights into the investigation of the synergic pattern of the co-culture system, we conducted a comparative iTRAQ-2-D-LC-MS/MS-based proteomic analysis of K. vulgare grown under reduced glutathione. Principal component analysis of proteomic data showed that after the addition of glutathione, proteins for thiamin/thiamin pyrophosphate (TPP) transport, glutathione transport and the maintenance of membrane integrity, together with several membrane-bound dehydrogenases had significant up-regulation. Besides, several proteins participating in the pentose phosphate pathway and tricarboxylic acid cycle were also up-regulated. Additionally, proteins combating intracellular reactive oxygen species were also up-regulated, which similarly occurred in K. vulgare when the co-cultured B. megaterium cells lysed from our former research results. This study reveals the demand for transmembrane transport of substrates, especially thiamin, and the demand for antioxidant protection of K. vulgare.
authors.affiliation: Key Laboratory of Systems Bioengineering, Ministry of Education and Department of Pharmaceutical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, People's Republic of China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Ma
authors.forename: Weiwen
authors.initials: W
authors.lastname: Zhang
authors.forename: Lu
authors.initials: L
authors.lastname: Zhang
authors.forename: Bin
authors.initials: B
authors.lastname: Qiao
authors.forename: Chensong
authors.initials: C
authors.lastname: Pan
authors.forename: Hong
authors.initials: H
authors.lastname: Yi
authors.forename: Lili
authors.initials: L
authors.lastname: Wang
authors.forename: Ying-jin
authors.initials: YJ
authors.lastname: Yuan
mesh_terms: D000975:Antioxidants / Q000737:chemistry*; D001205:Ascorbic Acid / Q000737:chemistry*; D018920:Coculture Techniques; D005285:Fermentation; D005978:Glutathione / Q000737:chemistry* / Q000378:metabolism; D008855:Microscopy, Electron, Scanning / Q000379:methods; D046529:Microscopy, Electron, Transmission / Q000379:methods; D008954:Models, Biological; D025341:Principal Component Analysis; D040901:Proteomics / Q000379:methods*; D017382:Reactive Oxygen Species; D041902:Rhodobacteraceae / Q000235:genetics* / Q000378:metabolism*; D013831:Thiamine / Q000737:chemistry*; D015854:Up-Regulation
chemical_list: D000975:Antioxidants; D017382:Reactive Oxygen Species; D005978:Glutathione; D001205:Ascorbic Acid; D013831:Thiamine