Phenotype profiling of single gene deletion mutants of E. coli using Biolog technology.

Phenotype MicroArray (PM) technology is high-throughput phenotyping system and is directly applicable to assay the effects of genetic changes in cells. In this study, we performed comprehensive PM analysis using single gene deletion mutants of central metabolic pathway and related genes. To elucidate the structure of central metabolic networks in Escherichia coli K-12, we focused 288 different PM conditions of carbon and nitrogen sources and performed bioinformatic analysis. For data processing, we employed noise reduction procedures. The distance between each of the mutants was defined by Manhattan distance and agglomerative Ward's hierarchical method was applied for clustering analysis. As a result, five clusters were revealed which represented to activate or repress cellular respiratory activities. Furthermore, the results might suggest that Glyceraldehyde-3P plays a key role as a molecular switch of central metabolic network.