Phosphoproteomic analysis of Methanohalophilus portucalensis FDF1T identified the role of protein phosphorylation in methanogenesis and osmoregulation

• DOI: 10.1038/srep29013
• Publication Date: 2016-06-30T09:24:35Z
• Authors: Wan-Ling Wu; Shu-Jung Lai; Jhih-Tian Yang; Jeffy Chern; Suh-Yuen Liang; Chi-Chi Chou; Chih-Horng Kuo; Mei-Chin Lai; Shih-Hsiung Wu
• Keywords: Phosphoproteomics; Osmolyte; Osmoregulation; Phosphopeptide

Abstract Methanogens have gained much attention for their metabolic product, methane, which could be an energy substitute but also contributes to the greenhouse effect. One factor that controls methane emission, reversible protein phosphorylation, is a crucial signaling switch and phosphoproteomics has become powerful tool large-scale surveying. Here, we conducted first phosphorylation-mediated regulation study in halophilic Methanohalophilus portucalensis FDF1 T , model strain studying stress response mechanisms osmoadaptation. A shotgun approach MS-based analysis identified 149 unique phosphoproteins. Among them, 26% participated methanogenesis osmolytes biosynthesis pathways. Of note, uncovered phosphorylation might modulate pyrrolysine (Pyl) incorporation Pyl-mediated methylotrophic methanogenesis. Furthermore, heterologous expression of glycine sarcosine N-methyltransferase (GSMT) mutant derivatives osmosensitive Escherichia coli MKH13 revealed nonphosphorylated T68A resulted increased salt tolerance. In contrast, mimic phosphorylated T68D proved defective both enzymatic activity salinity tolerance growth. Our provides new insights into modification as role osmoadaptation methanoarchaea, promoting biogas production or reducing future emission global warming climate change.