A Model for Carbohydrate Metabolism in the Diatom Phaeodactylum tricornutum Deduced from Comparative Whole Genome Analysis

• DOI: 10.1371/journal.pone.0001426
• Publication Date: 2008-01-08T22:38:54Z
• Authors: Peter G. Kroth; Anthony Chiovitti; Ansgar Gruber; Veronique Martin-...; Thomas Mock; Micaela Schnitzle...; Michele S. Stanley; Aaron Kaplan; Lise Caron; Till Weber; Uma Maheswari; E. Virginia Armbrust; Chris Bowler
• Keywords: Phaeodactylum tricornutum; Thalassiosira pseudonana; Carbon fixation

Diatoms are unicellular algae responsible for approximately 20% of global carbon fixation. Their evolution by secondary endocytobiosis resulted in a complex cellular structure and metabolism compared to with primary plastids.The whole genome sequence the diatom Phaeodactylum tricornutum has recently been completed. We identified annotated genes enzymes involved carbohydrate pathways based on extensive EST support comparison second diatom, Thalassiosira pseudonana. Protein localization mitochondria was predicted similarities mitochondrial motifs other eukaryotes, whereas protein plastids presence signal peptide combination plastid previously shown be required diatoms. potentially C4-like photosynthesis P. and, basis sequence-based putative relevant proteins, discuss possible differences concentrating mechanisms CO(2) fixation between two also encoding photorespiration one interesting exception: glycerate kinase not found either or T. Various Calvin cycle were up five different isoforms, distributed plastids, cytosol. store energy as lipids chrysolaminaran (a beta-1,3-glucan) outside plastids. various beta-glucanases large membrane-bound glucan synthases. Interestingly most glucanases appear contain C-terminal anchor domains that may attach membranes.Here we present detailed synthesis diatoms sequences pseudonana tricornutum. This model provides novel insights into acquisition dissolved inorganic metabolic diatoms, which is significance an improved understanding cycles.