title: High-yield production of extracellular type-I cellulose by the cyanobacterium Synechococcus sp. PCC 7002.
abstract: Cellulose synthase, encoded by the cesA gene, is responsible for the synthesis of cellulose in nature. We show that the cell wall of the cyanobacterium Synechococcus sp. PCC 7002 naturally contains cellulose. Cellulose occurs as a possibly laminated layer between the inner and outer membrane, as well as being an important component of the extracellular glycocalyx in this cyanobacterium. Overexpression of six genes, cmc-ccp-cesAB-cesC-cesD-bgl, from Gluconacetobacter xylinus in Synechococcus sp. PCC 7002 resulted in very high-yield production of extracellular type-I cellulose. High-level cellulose production only occurred when the native cesA gene was inactivated and when cells were grown at low salinity. This system provides a method for the production of lignin-free cellulose from sunlight and CO2 for biofuel production and other biotechnological applications.
authors.affiliation: State Key Laboratory of Protein and Plant Genetic Engineering, College of Life Sciences, Peking University, Beijing, China; Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, USA.
authors.forename: Chi
authors.initials: C
authors.lastname: Zhao
authors.affiliation: Department of Biochemistry and Molecular Biology, The Pennsylvania State University , University Park, PA, USA.
authors.forename: Zhongkui
authors.initials: Z
authors.lastname: Li
authors.affiliation: CAS Key Laboratory of Phycology, Institute of Hydrobiology, Chinese Academy of Sciences , Wuhan, Hubei, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Li
authors.affiliation: State Key Laboratory of Protein and Plant Genetic Engineering, College of Life Sciences, Peking University , Beijing, China.
authors.forename: Yingjiao
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, USA; Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT, USA.
authors.forename: Donald A
authors.initials: DA
authors.lastname: Bryant
authors.affiliation: State Key Laboratory of Protein and Plant Genetic Engineering, College of Life Sciences, Peking University, Beijing, China; CAS Key Laboratory of Phycology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, China.
authors.forename: Jindong
authors.initials: J
authors.lastname: Zhao
keywords: bioethanol; cell wall; cellulose; photosynthesis; synthetic biology