초록
<P><B>ABSTRACT</B></P><P>3‐Hydroxypropionic acid (3‐HP) can be produced from glycerol through two sequential enzymatic reactions that are catalyzed by a coenzyme B<SUB>12</SUB>‐dependent glycerol dehydratase and an NAD(P)<SUP>+</SUP>‐dependent aldehyde dehydrogenase (ALDH), respectively. <I>Pseudomonas denitrificans</I> synthesizes coenzyme B<SUB>12</SUB> under aerobic conditions, where NAD(P)<SUP>+</SUP> is regenerated efficiently. Hence, it is considered an ideal host for the production of 3‐HP from glycerol under aerobic conditions. In this study, recombinant strains of <I>P. denitrificans</I> were developed and their potential for the production of 3‐HP from glycerol was evaluated. When the enzymes, glycerol dehydratase (DhaB) and glycerol dehydratase reactivase (GdrAB), of <I>Klebsiella pneumoniae</I> were expressed heterologously, <I>P. denitrificans</I> could produce 3‐HP at 37.7 mmol/L with 62% (mol/mol) yield on glycerol. Glucose was required as the carbon and energy sources for cell growth. The overexpression of heterologous ALDH was not essential; however, the titer and yield of 3‐HP were improved to 54.7 mmol/L and 67% (mol/mol), respectively, when an ALDH gene (<I>puuC</I>) from <I>K. pneumoniae</I> was overexpressed. One serious drawback hindering the use of <I>P. denitrificans</I> as a recombinant host for 3‐HP production is that it oxidizes 3‐HP to malonate and utilizes 3‐HP as a carbon source for growth. This is the first report on the development and use of recombinant <I>P. denitrificans</I> for 3‐HP production from glycerol. Biotechnol. Bioeng. 2013;110: 3177–3187. © 2013 Wiley Periodicals, Inc.</P>