Acetylome Profiling Reveals Extensive Lysine Acetylation of the Fatty Acid Metabolism Pathway in the Diatom Phaeodactylum tricornutum

Abstract

Summary Nε -lysine acetylation represents a highly dynamic and reversibly regulated post-translational modification widespread in almost all organisms, and plays important roles for regulation of protein function in diverse metabolic pathways. However, little is known about the role of lysine acetylation in photosynthetic eukaryotic microalgae. We integrated proteomic approaches to comprehensively characterize the lysine acetylome in the model diatom Phaeodactylum tricornutum. In total, 2324 acetylation sites from 1220 acetylated proteins were identified, representing the largest dataset of the lysine acetylome in plants to date. Almost all enzymes involved in fatty acid synthesis were found to be lysine acetylated. Six putative lysine acetylation sites were identified in a plastid-localized long-chain acyl-CoA synthetase. Site-directed mutagenesis and site-specific incorporation of N-acetyllysine in acyl-CoA synthetase show that acetylation at K407 and K425 increases its enzyme activity. Moreover, the nonenzymatically catalyzed overall hyperacetylation of acyl-CoA synthetase by acetyl-phosphate can be effectively deacetylated and reversed by a sirtuin-type NAD + -dependent deacetylase with subcellular localization of both the plastid and nucleus in Phaeodactylum. This work indicates the regulation of acyl-CoA synthetase activity by site-specific lysine acetylation and highlights the potential regulation of fatty acid metabolism by lysine actetylation in the plastid of the diatom Phaeodactylum.4

Enhanced triacylglycerol production in the diatom Phaeodactylum tricornutum by inactivation of a Hotdog-fold thioesterase gene using TALEN-based targeted mutagenesis

“…Protein samples were subjected to standard SDS-PAGE and transferred to PVDF membranes (GE, Healthcare, Pittsburgh, USA) in 25 mM Tris, 192 mM glycine, and 20% methanol. Immunoblot was performed as described in Chen et al [ 52 ] using α-ptTES1 antibody. The signals were visualized using the method of chemiluminescence detection.…”

Genome Annotation of a Model Diatom Phaeodactylum tricornutum Using an Integrated Proteogenomic Pipeline

“…We previously reported a phosphoproteomic and acetylomic analysis of P. tricornutum (Chen et al, 2014(Chen et al, , 2018. However, little is known about other PTMs in P. tricornutum.…”

“…PTMs are dynamic cellular processes that regulate diverse protein properties in all known living organisms (Ngounou Wetie et al, 2014;Battchikova et al, 2015;Chicooree et al, 2015;Schwammle et al, 2015). It is well established that many PTM events are extensively involved in metabolic pathways and stress responses in P. tricornutum (Lepetit et al, 2013;Chen et al, 2014Chen et al, , 2018Rosenwasser et al, 2014;Veluchamy et al, 2015). Here, we performed a systematic analysis of PTM events in P. tricornutum and explored their potential functions in the response to high light intensity.…”

Comprehensive analysis of the lysine acetylome in Aeromonas hydrophila reveals cross-talk between lysine acetylation and succinylation in LuxS

“…Of these PTM sites, lysine is the most commonly modified amino acid residue, with only a single ionic interaction formed, thus offering more functional flexibility following acetylation, methylation, or ubiquitination [3]. Of these potential modifications, lysine acetylation is one of the most common [4]. Numerous studies have reported that this modification is widespread in both eukaryotes and prokaryotes and participates in the regulation of multiple complicated metabolic pathways [5].…”