Discovery and Engineering of an Aldehyde Tolerant 2-deoxy-D-ribose 5-phosphate Aldolase (DERA) from Pectobacterium atrosepticum

HARIDAS, MEERA; BISTERFELD, CAROLIN; CHEN, LE MIN; MARSDEN, STEFAN R.; TONIN, FABIO; MÉDICI, ROSARIO; IRIBARREN, ADOLFO; LEWKOWICZ, ELIZABETH; HAGEDOORN, PETER-LEON; HANEFELD, ULF; ABDELRAHEEM, EMAN

Catalysts

MDPI

Lugar: Basel; Año: 2020 vol. 10

DERA (2-Deoxy-D-ribose 5-phosphate aldolase) is the only known aldolase that acceptstwo aldehyde substrates, which makes it an attractive catalyst for the synthesis of a chiral polyolmotif that is present in several pharmaceuticals, such as atorvastatin and pravastatin. However,inactivation of the enzyme in the presence of aldehydes hinders its practical application. Whole cells ofPectobacterium atrosepticum were reported to exhibit good tolerance toward acetaldehyde and to aord2-deoxyribose 5-phosphate with good yields. The DERA gene (PaDERA) was identified, and both thewild-type and a C49M mutant were heterologously expressed in Escherichia coli. The purificationprotocol was optimized and an initial biochemical characterization was conducted. Unlike otherDERAs, which show a maximal activity between pH 4.0 and 7.5, PaDERA presented an optimumpH in the alkaline range between 8.0 and 9.0. This could warrant its use for specific syntheses in thefuture. PaDERA also displayed fourfold higher specific activity than DERA from E. coli (EcDERA)and displayed a promising acetaldehyde resistance outside the whole-cell environment. The C49Mmutation, which was previously identified to increase acetaldehyde tolerance in EcDERA, also led tosignificant improvements in the acetaldehyde tolerance of PaDERA.