title: Export of extracellular polysaccharides modulates adherence of the Cyanobacterium synechocystis.
abstract: The field of cyanobacterial biofuel production is advancing rapidly, yet we know little of the basic biology of these organisms outside of their photosynthetic pathways. We aimed to gain a greater understanding of how the cyanobacterium Synechocystis PCC 6803 (Synechocystis, hereafter) modulates its cell surface. Such understanding will allow for the creation of mutants that autoflocculate in a regulated way, thus avoiding energy intensive centrifugation in the creation of biofuels. We constructed mutant strains lacking genes predicted to function in carbohydrate transport or synthesis. Strains with gene deletions of slr0977 (predicted to encode a permease component of an ABC transporter), slr0982 (predicted to encode an ATP binding component of an ABC transporter) and slr1610 (predicted to encode a methyltransferase) demonstrated flocculent phenotypes and increased adherence to glass. Upon bioinformatic inspection, the gene products of slr0977, slr0982, and slr1610 appear to function in O-antigen (OAg) transport and synthesis. However, the analysis provided here demonstrated no differences between OAg purified from wild-type and mutants. However, exopolysaccharides (EPS) purified from mutants were altered in composition when compared to wild-type. Our data suggest that there are multiple means to modulate the cell surface of Synechocystis by disrupting different combinations of ABC transporters and/or glycosyl transferases. Further understanding of these mechanisms may allow for the development of industrially and ecologically useful strains of cyanobacteria. Additionally, these data imply that many cyanobacterial gene products may possess as-yet undiscovered functions, and are meritorious of further study.
authors.affiliation: Biodesign Institute, Center for Infectious Diseases and Vaccinology, Arizona State University, Tempe, Arizona, United States of America.
authors.forename: Michael L
authors.initials: ML
authors.lastname: Fisher
authors.forename: Rebecca
authors.initials: R
authors.lastname: Allen
authors.forename: Yingqin
authors.initials: Y
authors.lastname: Luo
authors.forename: Roy
authors.initials: R
authors.lastname: Curtiss
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000172:deficiency / Q000235:genetics; D001422:Bacterial Adhesion; D056804:Biofuels; D001692:Biological Transport; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D005898:Glass; D007218:Industrial Microbiology; D060847:Metabolic Engineering; D008780:Methyltransferases / Q000172:deficiency / Q000235:genetics; D005810:Multigene Family; D019081:O Antigens / Q000235:genetics* / Q000378:metabolism; D046939:Synechocystis / Q000235:genetics* / Q000378:metabolism
chemical_list: D018528:ATP-Binding Cassette Transporters; D056804:Biofuels; D019081:O Antigens; D008780:Methyltransferases
references.citation: PLoS One. 2013;8(2):e55564
references.pmid: 23405172
references.citation: Proc Natl Acad Sci U S A. 2011 Apr 26;108(17):6905-8
references.pmid: 21482802
references.citation: J Integr Plant Biol. 2009 Feb;51(2):194-200
references.pmid: 19200158
references.citation: Trends Microbiol. 1996 Dec;4(12):495-503
references.pmid: 9004408
references.citation: Microbiology (Reading). 2001 Jan;147(Pt 1):3-9
references.pmid: 11160795
references.citation: J Gen Microbiol. 1968 Apr;51(2):203-9
references.pmid: 5652096
references.citation: J Clin Microbiol. 1986 Sep;24(3):330-2
references.pmid: 3489731
references.citation: Plant Cell Physiol. 1997 Nov;38(11):1171-6
references.pmid: 9435137
references.citation: J Bacteriol. 2005 Oct;187(20):6883-92
references.pmid: 16199557
references.citation: Biochem Biophys Res Commun. 1998 Apr 17;245(2):572-82
references.pmid: 9571197
references.citation: Proc Natl Acad Sci U S A. 2009 Dec 22;106(51):21550-4
references.pmid: 19995962
references.citation: Bioresour Technol. 2009 Dec;100(23):5588-93
references.pmid: 19560345
references.citation: Microbiology (Reading). 2011 Feb;157(Pt 2):451-458
references.pmid: 20966085
references.citation: J Bacteriol. 1997 May;179(9):2884-91
references.pmid: 9139904
references.citation: Analyst. 2000 Apr;125(4):651-6
references.pmid: 10892021
references.citation: Carbohydr Res. 2003 Nov 14;338(23):2503-19
references.pmid: 14670712
references.citation: J Biol Chem. 1991 Jun 15;266(17):11111-5
references.pmid: 1904061
references.citation: Nucleic Acids Res. 2010 Jan;38(Database issue):D379-81
references.pmid: 19880388
references.citation: Gene. 1989 Apr 15;77(1):51-9
references.pmid: 2744487
references.citation: J Biol Chem. 2005 Aug 26;280(34):30310-9
references.pmid: 15980069
references.citation: Microbiol Mol Biol Rev. 2010 Sep;74(3):341-62
references.pmid: 20805402
references.citation: Anal Biochem. 1982 Jan 1;119(1):115-9
references.pmid: 6176137
references.citation: J Biotechnol. 2012 Nov 15;161(4):445-9
references.pmid: 22944207
references.citation: Proc Natl Acad Sci U S A. 2011 Apr 26;108(17):6899-904
references.pmid: 21482809
references.citation: Microbiol Mol Biol Rev. 2003 Dec;67(4):593-656
references.pmid: 14665678
references.citation: Annu Rev Microbiol. 2000;54:49-79
references.pmid: 11018124
references.citation: Microbiol Mol Biol Rev. 2000 Dec;64(4):847-67
references.pmid: 11104821
references.citation: Mol Microbiol. 1991 Jun;5(6):1447-57
references.pmid: 1686293
references.citation: Nucleic Acids Res. 2000 Jan 1;28(1):33-6
references.pmid: 10592175
references.citation: J Bacteriol. 1995 Apr;177(8):2178-87
references.pmid: 7536735
references.citation: Methods Enzymol. 1994;230:1-15
references.pmid: 8139491
references.citation: Bioresour Technol. 2010 Dec;101(24):9742-8
references.pmid: 20719501
references.citation: Appl Environ Microbiol. 2008 May;74(9):2797-804
references.pmid: 18326679
references.citation: Environ Sci Pollut Res Int. 2010 Mar;17(3):595-602
references.pmid: 19727881
references.citation: J Bacteriol. 2007 Nov;189(22):7945-7
references.pmid: 17675377