Dataset Information

The Plastid Proteome of the Nonphotosynthetic Chlorophycean Alga Polytomella parva

ABSTRACT: The unicellular, free-living, nonphotosynthetic chlorophycean alga Polytomella parva, closely related to Chlamydomonas reinhardtii and Volvox carteri, contains colorless, starch-storing plastids. The P. parva plastids lack all light-dependent processes but maintain crucial metabolic pathways. The colorless alga also lacks a plastid genome, meaning no transcription or translation should occur inside the organelle. Here, using an algal fraction enriched in plastids as well as publicly available transcriptome data, we provide a proteomic characterization of the P. parva plastid, ultimately identifying several plastid proteins, both by mass spectrometry and bioinformatic analyses. Altogether these results led us to propose a plastid proteome for P. parva, i.e., a set of proteins that participate in carbohydrate metabolism; in the synthesis and degradation of starch, amino acids and lipids; in the biosynthesis of terpenoids and tetrapyrroles; in solute transport and protein translocation; and in redox homeostasis. This is the first detailed plastid proteome from a unicellular, free-living colorless alga.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Polytomella Parva

SUBMITTER: Alfredo Cabrera-Orefice

LAB HEAD: Dr. Diego González-Halphen

PROVIDER: PXD022051 | Pride | 2020-12-10

REPOSITORIES: Pride

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The plastid proteome of the nonphotosynthetic chlorophycean alga Polytomella parva.

Fuentes-Ramírez Emma O EO Vázquez-Acevedo Miriam M Cabrera-Orefice Alfredo A Guerrero-Castillo Sergio S González-Halphen Diego D

Microbiological research 20201128

The unicellular, free-living, nonphotosynthetic chlorophycean alga Polytomella parva, closely related to Chlamydomonas reinhardtii and Volvox carteri, contains colorless, starch-storing plastids. The P. parva plastids lack all light-dependent processes but maintain crucial metabolic pathways. The colorless alga also lacks a plastid genome, meaning no transcription or translation should occur inside the organelle. Here, using an algal fraction enriched in plastids as well as publicly available tr ...[more]

PMID: 33285428

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