Investigating cellular responses during photohydrogen production by the marine microalga Tetraselmis subcordiformis by quantitative proteome analysis

The marine microalga Tetraselmis subcordiformis could photoproduce hydrogen under the regulation of carbonyl cyanide m-chlorophenylhydrazone (CCCP), and a hydrogen production process kinetic analysis was characterized by two peaks, suggesting that two distinct mechanisms might exist in this alga. Therefore, 2D nanoliquid chromatography-tandem mass spectrometry (LC-MS/MS)was introduced to analyze the proteome of samples from different time points. A total of 912 proteins were identified, providing a global view of the cellular responses at the proteomic level. These proteins can be divided into multiple functional groups including stress responses, energy metabolism and redox homeostasis. The quantitative proteomic data provided more details on the electron donors for hydrogen production. During the first stage, photosystem II produced electrons for hydrogen production; during the second stage, metabolites were the major electron donors via nonphotochemical plastoquinone reduction by NADH dehydrogenase.