title: Knockdown of PsbO leads to induction of HydA and production of photobiological H2 in the green alga Chlorella sp. DT.
abstract: Green algae are able to convert solar energy to H2 via the photosynthetic electron transport pathway under certain conditions. Algal hydrogenase (HydA, encoded by HYDA) is in charge of catalyzing the reaction: 2H(+)+2e(-)↔H2 but usually inhibited by O2, a byproduct of photosynthesis. The aim of this study was to knockdown PsbO (encoded by psbO), a subunit concerned with O2 evolution, so that it would lead to HydA induction. The alga, Chlorella sp. DT, was then transformed with short interference RNA antisense-psbO (siRNA-psbO) fragments. The algal mutants were selected by checking for the existence of siRNA-psbO fragments in their genomes and the low amount of PsbO proteins. The HYDA transcription and the HydA expression were observed in the PsbO-knockdown mutants. Under semi-aerobic condition, PsbO-knockdown mutants could photobiologically produce H2 which increased by as much as 10-fold in comparison to the wild type.
authors.affiliation: Department of Life Sciences, National Chung Hsing University, Taichung 402, Taiwan.
authors.forename: Hsin-Di
authors.initials: HD
authors.lastname: Lin
authors.forename: Bang-Hung
authors.initials: BH
authors.lastname: Liu
authors.forename: Ting-Ting
authors.initials: TT
authors.lastname: Kuo
authors.forename: Hsieh-Chin
authors.initials: HC
authors.lastname: Tsai
authors.forename: Teng-Yung
authors.initials: TY
authors.lastname: Feng
authors.forename: Chieh-Chen
authors.initials: CC
authors.lastname: Huang
authors.forename: Lee-Feng
authors.initials: LF
authors.lastname: Chien
mesh_terms: D001483:Base Sequence; D015153:Blotting, Western; D002708:Chlorella / Q000235:genetics / Q000378:metabolism*; D017931:DNA Primers; D055785:Gene Knockdown Techniques; D010940:Plant Proteins / Q000096:biosynthesis* / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D034741:RNA, Small Interfering / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D017931:DNA Primers; D010940:Plant Proteins; D012333:RNA, Messenger; D034741:RNA, Small Interfering
keywords: Green alga; HydA; Induction; Knockdown; PsbO