Microbial Proteomics: Archaea to Cyanobacteria

Abstract

This Journal is Korean Society of Photoscience 2012 C 57 Thermococcus onnurineus NA1, sulfur reducing hyperthermophilic archaeon, is capable of H ‐ 2 producing growth and ‐ considered to be hydrogenogenic carboxydotrophy. Utilization of formate as a sole energy source has been well studied in T. onnurineus NA1. However, whether formate could be used as its carbon source remains unanswered question. To obtain a global view on the metabolic characteristics in H2 producing growth, the quantitative proteome analysis of ‐ T. onnurineus NA1 grown on formate, CO and starch was performed by combining 1DSDS PAGE with nano UPLCMS ‐ ‐ E method. Our data propose that CO could be utilized as its sole energy source via electron transport mechanism to produce H2. Additionally, our data propose that CO2 produced from catabolic pathway or CO oxidation by CODH and CO‐ induced hydrogenase activities could subsequently be assimilated into the organic carbon. Overall, proteomic comparison of formate and COgrown cells with starch grown cells revealed that one carbon compound such as formate and CO ‐ ‐ ‐ could be utilized as an efficient substrate to provide cellular carbon and/or energy in T. onnurineus NA1. Unicellular Gloeobacter violaceus PCC 7421 is a Gramnegative photoautotrophic cyanobacterium. ‐ Gloeobacter violaceus PCC 7421 was divided at very early point of the phylogenetic tree and contained very primitive and unusual features like lack of thylakoidal membrane and missing of some photosystem components. In this study we performed proteomic analysis of Gloeobacter violaceus PCC 7421 through the following two approaches. First, we separate the total, soluble and insoluble fractions of Gloeobacter violaceus PCC 7421 and performed the twodimensional ‐ electrophoresis (2DE). Second, insoluble fractions were analyzed by FTICR mass spectrometer. After 2DE separation ‐ ‐ ‐ in gel digested spots were identified by the MALDI/TOF/TOF analysis about 115, 73 and 21 proteins were identified ‐ from total, soluble and insoluble fractions, respectively. Also insoluble fraction was digested using both chemical and tryptic in solution digestion methods to obtain the more peptides with transmembrane regions. Following the FTICR ‐ ‐ analysis 785 proteins were identified and among them 139 proteins with 1 or more (~14) transmembrane domains were analyzed using TMHMM program. Considering the number of theoretical proteins (965) with 1~ TM about 14.4% of that proteins were found. Through these proteomic analyses we could determine the protein preparation methods and provide the 2DE map of ‐ Gloeobacter violaceus PCC 7421. Microbial Proteomics: Archaea to Cyanobacteria