Acetylation Proteomics Research Of Saccharopolyspora Erythraea

Lysine acetylation is a dynamic reversible post-translational modification （PTM）, which is known to play an important role in regulating activity of many key enzymes in eukaryotes and prokaryotes. Acetylproteome studies have also been performed on some prokaryotes, including Escherichia coli, Bacillus subtilis, Salmonella enterica, Geobacillus kaustophilus, Erwinia amylovora, and Thermus thermophiles. However, until now there have been no data for actinomycetes which are mainly producers of therapeutic antibiotics. Acetylation levels in vivo changes regulated by acetyltransferase/deacetylase system.In this study, we used two methods of proteomics to analysis acetylation of erythromycin producer Saccharopolyspora erythraea. On one hand, Combination anti-acetyllysine antibody immune-affinity of acetyl-peptides followed by nano-HPLC/MS/MS analysis, we identified664unique lysine acetylated sites on363proteins. The acetylated proteins are involved in many biological processes, such as protein synthesis, glycolysis/gluconeogenesis, TCA cycle, fatty acid metabolism, secondary metabolism and the precursor synthesis. We characterized the acetylproteome and analysed in detail the impact of the acetylation on diverse cellular functions according to Gene Ontology and KEGG pathway. The four motif sequences around acetylation site （KACH, KACY, KACXXXXR, and KACXXXXK） were found in S. erythraea acetylproteome. Interaction networks and high confident domains architectures of acetylated proteins were analyzed by using bioinformatics tools, and found four high enrichment domains. On the other hand, under different culture conditions, we compared wild type of S. erythraea with two knockout sterilization （ASACE₅148and ASACE₃798） in growth curve, sporulation, producing of red pigment and erythromycin. While combining two-dimensional fluorescence difference gel electrophoresis and MALDI-TOF-TOF to compare differential proteins among the three type S. erythraea, and selected96differentially expressed proteins whose fold change absolute value are more than2. Moreover, we initially classified the differential proteins by Gene ontology （including cell component, molecular function and biological process） and metabolism pathways.As to conservation of acetylation, these studies allow us to understand acetylation of actinomyces, expand current knowledge of the bacterial acetylproteome andprovide the insight for uncovering the function of acetylation in primary and secondary metabolism. In the meanwhile, it provides a guiding role to acetylation research of others actinomyces in the future.