Biochemical and genetic characterization of a novel enzyme of pentitol metabolism: d-arabitol-phosphate dehydrogenase

Abstract

An enzyme with a specificity that has not been described previously, D-arabitol-phosphate dehydrogenase (APDH), has been purified from cell lysate of Enterococcus avium. SDS/PAGE indicated that the enzyme had a molecular mass of 41+/-2 kDa, whereas a molecular mass of 160+/-5 kDa was observed under non-denaturing conditions, implying that the APDH may exist as a tetramer with identical subunits. Purified APDH was found to have a narrow substrate specificity, converting only D-arabitol 1-phosphate and D-arabitol 5-phosphate into xylulose 5-phosphate and ribulose 5-phosphate, respectively, in the oxidative reaction. Both NAD(+) and NADP(+) were accepted as cofactors. Based on the partial protein sequences, the APDH gene was cloned. Homology comparisons place APDH within the medium-range dehydrogenase family. Unlike most members of this family, APDH requires Mn(2+) but no Zn(2+) for enzymic activity. The DNA sequence surrounding the gene suggests that it belongs to an operon that also contains several components of phosphotransferase system. Both biochemical evidence and protein sequence homology comparisons indicate that similar enzymes are widespread among the Gram-positive bacteria. Their apparent biological role is to participate in arabitol catabolism via the 'arabitol phosphate route', similar to the ribitol and xylitol catabolic routes described previously.

Transport and Catabolism of Pentitols by Listeria monocytogenes

“…Bacteria from most phyla, such as the proteobacteria Klebsiella pneumoniae [Heuel et al, 1997] and Pseudomonas fluorescens [Brün ker et al, 1998], the actinobacterium Corynebacterium glutamicum [Laslo et al, 2012], and the firmicutes Enterococcus avium [Povelainen et al, 2003] and Listeria monocytogenes [Saklani-Jusforgues et al, 2001] utilize D -arabitol as a carbon and energy source. The γ-proteobacterium K. pneumoniae and the actinobacterium C. glutamicum take up D -arabitol via closely related transporters of the major facilitator superfamily (DalT and RbtT, respectively).…”

Utilization of d -Ribitol by Lactobacillus casei BL23 Requires a Mannose-Type Phosphotransferase System and Three Catabolic Enzymes

“…The genes encoding the three PTS components are followed by two genes encoding potential D-arabinitol-5-P dehydrogenases. A D-arabinitol-phosphate dehydrogenase oxidizing D-arabinitol-1-P to L-xylulose-5-P and D-arabinitol-5-P to ribulose-5-P was also detected in Enterococcus avium (47). This enzyme uses NAD ϩ as well as NADP ϩ as cofactors and depends on Mn 2ϩ and not Zn 2ϩ .…”

“…It is therefore tempting to assume that this PTS transports and phosphorylates either L-ribitol or L-arabinitol, which would subsequently be oxidized to D-ribulose-5-P. Indeed, the dehydrogenase of the xpk-araD region shows the most significant similarity to the E. avium arabinitol-phosphate dehydrogenase (47). Pentitols with the L-configuration are very rare in nature (54), but at least L-arabinitol has recently been shown to be utilized by plant-symbiotic bacteria (13).…”

“…This enzyme uses NAD ϩ as well as NADP ϩ as cofactors and depends on Mn 2ϩ and not Zn 2ϩ . The gene encoding this enzyme is located in an operon containing also the genes for the components of a galactitol PTS (47). In addition, the enterococcal enzyme exhibits 64% sequence identity to one of the presumed LCABL_29190).…”

Metabolic Engineering of Saccharomyces cerevisiae for Conversion of d -Glucose to Xylitol and Other Five-Carbon Sugars and Sugar Alcohols

“…DXylulose 5-phosphate and D-ribulose 5-phosphate also serve as precursors for D-arabitol when the D-arabitol phosphate dehydrogenase from Enterococcus avium is applied (22,24). DRibose, a drug precursor, and erythritol, a sweetener, are commercially produced from D-glucose by the Bacillus, Aureobasidium, and Torula species with a yield of almost 50% (wt/ wt) of consumed D-glucose (5,12,14,16).…”