Tagaturonate-fructuronate epimerase UxaE, a novel enzyme in the hexuronate catabolic network inThermotoga maritima

Irina A. Rodionova, David A. Scott, Nick V. Grishin, Andrei L. Osterman, Dmitry A. Rodionov
2012 Environmental Microbiology  
Thermotoga maritima is a marine hyperthermophilic microorganism that degrades a wide range of simple and complex carbohydrates including pectin and produces fermentative hydrogen at high yield. Galacturonate and glucuronate, two abundant hexuronic acids in pectin and xylan, respectively, are catabolized via committed metabolic pathways to supply carbon and energy for a variety of microorganisms. By a combination of bioinformatics and experimental techniques we identified a novel enzyme family
more » ... amed UxaE) catalysing a previously unknown reaction in the hexuronic acid catabolic pathway, epimerization of tagaturonate to fructuronate. The enzymatic activity of the purified recombinant tagaturonate epimerase from T. maritima was directly confirmed and kinetically characterized. Its function was also confirmed by genetic complementation of the growth of the Escherichia coli uxaB knockout mutant strain on * For correspondence. rodionov@burnham.org; Tel.
doi:10.1111/j.1462-2920.2012.02856.x pmid:22925190 pmcid:PMC4505799 fatcat:luduzrqelbezdppqyubuhygnpu