Genes and enzymes of ectoine biosynthesis in halotolerant methanotrophs

摘要: Ectoine (1,4,5,6-tetrahydro-2-methyl-4-pyrimidine carboxylic acid) is a widely distributed compatible solute accumulated by halophilic and halotolerant microorganisms to prevent osmotic stress in highly saline environments. as water keeping compound stabilizing biomolecules whole cells can be used scientific work, cosmetics, medicine. Detailed understanding of the organization/regulation ectoine biosynthetic pathway various producers an active area research. Here we review current knowledge on some genetic enzymatic aspects biosynthesis methanotrophs. By using PCR methodology, genes coding for specific enzymes biosynthesis, diaminobutyric acid (DABA) aminotransferase (EctB), DABA acetyltransferase (EctA), synthase (EctC), were identified several methanotrophic species. Organization these either ectABC or ectABC-ask operons, latter additionally encoding aspartate kinase isozyme (Ask), correlated well with methanotroph halotolerance intracellular level. A new gene, ectR1 MarR-like transcriptional regulatory protein EctR1, negatively controlling transcription was found upstream operon Methylomicrobium alcaliphilum 20Z. The ectR-like also methanol utilizers Methylophaga alcalica thalassica genomes nonmethylotrophic His(6)-tagged acetyltransferases from Mm. alcaliphilum, M. alcalica, purified enzyme properties correlate ecophysiologies bacteria. All discoveries should very helpful better mechanism this important natural compound, targeted metabolic engineering its producers.