Pleiotropic effect of sigE over‐expression on cell morphology, photosynthesis and hydrogen production in Synechocystis sp. PCC 6803. (19th September 2013)

• Record Type: Journal Article
• Authors: Osanai, Takashi; Kuwahara, Ayuko; Iijima, Hiroko; Toyooka, Kiminori; Sato, Mayuko; Tanaka, Kan; Ikeuchi, Masahiko; Saito, Kazuki; Hirai, Masami Yokota
• Is Part Of: Plant journal. Volume 76:Number 3(2013:Nov.)
• Page Start: 456
• Page End: 465
• Publication Date: 2013-09-19
• Subjects: Plant molecular biology -- Periodicals; Plant cells and tissues -- Periodicals; Botany -- Periodicals; 580
• DOI: 10.1111/tpj.12310
• Languages: English
• ISSNs: 0960-7412

Abstract

<abstract abstract-type="main" id="tpj12310-abs-0001"> <title>Summary</title> <p>Over‐expression of <italic>sigE</italic>, a gene encoding an RNA polymerase sigma factor in the unicellular cyanobacterium <italic>Synechocystis</italic> sp. PCC 6803, is known to activate sugar catabolism and bioplastic production. In this study, we investigated the effects of <italic>sigE</italic> over‐expression on cell morphology, photosynthesis and hydrogen production in this cyanobacterium. Transmission electron and scanning probe microscopic analyses revealed that <italic>sigE</italic> over‐expression increased the cell size, possibly as a result of aberrant cell division. Over‐expression of <italic>sigE</italic> reduced respiration and photosynthesis activities via changes in gene expression and chlorophyll fluorescence. Hydrogen production under micro‐oxic conditions is enhanced in <italic>sigE</italic> over‐expressing cells. Despite these pleiotropic phenotypes, the <italic>sigE</italic> over‐expressing strain showed normal cell viability under both nitrogen‐replete and nitrogen‐depleted conditions. These results provide insights into the inter‐relationship among metabolism, cell morphology, photosynthesis and hydrogen production in this unicellular cyanobacterium.</p> </abstract>