title: CO2reduction and organic compounds production by photosynthetic bacteria with surface displayed carbonic anhydrase and inducible expression of phosphoenolpyruvate carboxylase.
abstract: In Rhodobacter sphaeroides, carbonic anhydrase (CA; EC 4.2.1.1) is a zinc-containing metalloenzyme that catalyzes the reversible hydration of CO2to HCO3-while phosphoenolpyruvate carboxylase (PEPC; 4.1.1.31), an enzyme involved in the carbon metabolism that catalyzed the fixation of CO2to PEP, is a key factor for biological fixation of CO2and enhances the production of organic compounds. In this study, the recombinant R. sphaeroides with highly-expressed CA was developed based on a surface displayed system of CA (pJY-OmpCA) on the outer membrane of R. sphaeroides using outer membrane protein (Omp) in R. sphaeroides, Finally, two more different recombinant R. sphaeroides were developed, which transformed with a two-vector system harboring cytosolic expressed CA (pJY-OmpCA-CA)or PEPC (pJY-OMPCA-PEPC) in R. sphaeroides with surface displayed CA on the outer membrane. In case of recombinant R. sphaeroides with the pJY-OmpCA-PEPC, it has shown the highest CO2reduction efficiency and the production of several organic compounds (carotenoids, polyhydroxybutyrate, malic acid, succinic acid). It means that the surface displayed CA on the R. sphaeroides would accelerate the CO2-bicabonate conversion on the bacterial outer membrane. Moreover, inducible over-expression of PEPC with surface-displayed CA was successfully used to facilitate a rapider CO2reduction and quicker production of organic compounds.
authors.affiliation: Graduate School of Semiconductor and Chemical Engineering, Chonbuk National University, 567 Baekje-daero, Deokjin-Gu, Jeonju 54896, South Korea.
authors.forename: Ju-Yong
authors.initials: JY
authors.lastname: Park
authors.affiliation: School of Biological Sciences, Chungbuk National University, 1 Chungdae-ro, Seowon-Gu, Cheongju 28644, South Korea. Electronic address: kyh@chungbuk.ac.kr.
authors.forename: Yang-Hoon
authors.initials: YH
authors.lastname: Kim
authors.affiliation: Graduate School of Semiconductor and Chemical Engineering, Chonbuk National University, 567 Baekje-daero, Deokjin-Gu, Jeonju 54896, South Korea. Electronic address: jihomin@jbnu.ac.kr.
authors.forename: Jiho
authors.initials: J
authors.lastname: Min
mesh_terms: D002245:Carbon Dioxide / Q000378:metabolism*; D002256:Carbonic Anhydrases / Q000235:genetics / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D061505:Cell Surface Display Techniques / Q000379:methods; D006885:Hydroxybutyrates / Q000378:metabolism; D010730:Phosphoenolpyruvate Carboxylase / Q000235:genetics / Q000378:metabolism*; D010788:Photosynthesis; D011091:Polyesters / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012242:Rhodobacter sphaeroides / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D000094122:Polyhydroxybutyrates
chemical_list: D002245:Carbon Dioxide; D002256:Carbonic Anhydrases; D006885:Hydroxybutyrates; D010730:Phosphoenolpyruvate Carboxylase; D011091:Polyesters; D011993:Recombinant Fusion Proteins; C003182:poly-beta-hydroxybutyrate; D000094122:Polyhydroxybutyrates
keywords: CO(2) reduction; Carbonic anhydrase; Organic compounds production; Phosphoenolpyruvate carboxylase; Surface displayed CA