A gene of Aspergillus oryzae, ladA, which encodes L-arabinitol 4-dehydrogenase (EC 1.1.1.12), and its cDNA were cloned in Escherichia coli. The gene consisted of a 1209-bp coding region, interrupted by a 59-bp intron, which encoded a 382-amino-acid polypeptide (40,812 Da). The protein showed 67% identity to a well-studied L-arabinitol 4-dehydrogenase (Lad1) of Hypocrea jecorina. The cell-free extract of E. coli, which expressed ladA cDNA, showed L-arabinitol dehydrogenase activity with NAD+. It was also reactive for ribitol and xylitol.

Download full-text PDF

Source
http://dx.doi.org/10.1263/jbb.100.472DOI Listing

Publication Analysis

Top Keywords

l-arabinitol 4-dehydrogenase
12
aspergillus oryzae
8
cloning expression
4
expression nad+-dependent
4
l-arabinitol
4
nad+-dependent l-arabinitol
4
4-dehydrogenase gene
4
gene lada
4
lada aspergillus
4
oryzae gene
4

Similar Publications

Multi-enzymatic strategies have shown improvement in bioconversion during cofactor regeneration. In this study, purified l-arabinitol 4-dehydrogenase (LAD) and nicotinamide adenine dinucleotide oxidase (Nox) were immobilized via individual, mixed, and sequential co-immobilization approaches on magnetic nanoparticles, and were evaluated to enhance the conversion of l-arabinitol to l-xylulose. Initially, the immobilization of LAD or Nox on the nanoparticles resulted in a maximum immobilization yield and relative activity of 91.

View Article and Find Full Text PDF

We have recently developed a simple, reusable and coupled whole-cell biocatalytic system with the capability of cofactor regeneration and biocatalyst immobilization for improved production yield and sustained synthesis. Described herewith is the experimental procedure for the development of such a system consisting of two E. coli strains that express functionally complementary enzymes.

View Article and Find Full Text PDF

Role of a remote leucine residue in the catalytic function of polyol dehydrogenase.

Mol Biosyst

December 2014

Department of Chemical Engineering, 1 Hwayang-Dong, Gwangjin-Gu, Seoul 143-701, Republic of Korea.

Studies on the protein-metal binding sites have mainly focused on the residues immediately surrounding the reacting substrate, cofactors, and metal ions. The contribution of residues in remote layers to the highly optimized microenvironments of catalytic active sites is not well understood. To improve our understanding, the present study examined the role of remote residues on the structure and function of zinc-dependent polyol dehydrogenases.

View Article and Find Full Text PDF

pH-rate profiles of L-arabinitol 4-dehydrogenase from Hypocrea jecorina and its application in L-xylulose production.

Bioorg Med Chem Lett

January 2014

Department of Chemical Engineering, Konkuk University, Seoul 143-701, Republic of Korea; Institute of SK-KU Biomaterials, Konkuk University, Seoul 143-701, Republic of Korea. Electronic address:

Article Synopsis
  • Researchers cloned and overexpressed l-Arabinitol 4-dehydrogenase (HjLAD) from the fungus Hypocrea jecorina in E. coli.
  • They investigated the enzyme's kinetics for oxidizing l-arabinitol with NAD(+) at various pH levels, finding a high turnover number (kcat) of 4200 min(-1) and a catalytic efficiency (kcat/Km) of 290 mM(-1)min(-1).
  • HjLAD achieved the highest efficiency and turnover of any previously studied LAD and was successfully used to produce l-xylulose from arabinitol with an 86% yield.
View Article and Find Full Text PDF

L-Xylulose is a potential starting material for therapeutics. However, its translation into clinical practice has been hampered by its inherently low bioavailability. In addition, the high cost associated with the production of L-xylulose is a major factor hindering its rapid deployment beyond the laboratory.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!