An open reading frame CC1225 from the Caulobacter crescentus CB15 genome sequence belongs to the Gfo/Idh/MocA protein family and has 47 % amino acid sequence identity with the glucose-fructose oxidoreductase from Zymomonas mobilis (Zm GFOR). We expressed the ORF CC1225 in the yeast Saccharomyces cerevisiae and used a yeast strain expressing the gene coding for Zm GFOR as a reference. Cell extracts of strains overexpressing CC1225 (renamed as Cc aaor) showed some Zm GFOR type of activity, producing D-gluconate and D-sorbitol when a mixture of D-glucose and D-fructose was used as substrate. However, the activity in Cc aaor expressing strain was >100-fold lower compared to strains expressing Zm gfor. Interestingly, C. crescentus AAOR was clearly more efficient than the Zm GFOR in converting in vitro a single sugar substrate D-xylose (10 mM) to xylitol without an added cofactor, whereas this type of activity was very low with Zm GFOR. Furthermore, when cultured in the presence of D-xylose, the S. cerevisiae strain expressing Cc aaor produced nearly equal concentrations of D-xylonate and xylitol (12.5 g D-xylonate l(-1) and 11.5 g D-xylitol l(-1) from 26 g D-xylose l(-1)), whereas the control strain and strain expressing Zm gfor produced only D-xylitol (5 g l(-1)). Deletion of the gene encoding the major aldose reductase, Gre3p, did not affect xylitol production in the strain expressing Cc aaor, but decreased xylitol production in the strain expressing Zm gfor. In addition, expression of Cc aaor together with the D-xylonolactone lactonase encoding the gene xylC from C. crescentus slightly increased the final concentration and initial volumetric production rate of both D-xylonate and D-xylitol. These results suggest that C. crescentus AAOR is a novel type of oxidoreductase able to convert the single aldose substrate D-xylose to both its oxidized and reduced product.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4628093 | PMC |
http://dx.doi.org/10.1007/s00253-015-6878-5 | DOI Listing |
Microb Biotechnol
January 2025
Institute of Bio- and Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich GmbH, Jülich, Germany.
Glucose is the most abundant monosaccharide and a principal substrate in biotechnological production processes. In Pseudomonas, this sugar is either imported directly into the cytosol or first oxidised to gluconate in the periplasm. While gluconate is taken up via a proton-driven symporter, the import of glucose is mediated by an ABC-type transporter, and hence both require energy.
View Article and Find Full Text PDFJ Appl Microbiol
January 2025
College of Life Sciences, Nanjing Normal University, Nanjing 210023, China.
Aim: This study was dedicated to investigating the role of sulfur metabolic processes in sulfate-reducing bacteria in plant resistance to heavy metal contamination.
Methods And Results: We constructed sulfate-reducing bacterial communities based on the functional properties of sulfate-reducing strains, and then screened out the most effective sulfate-reducing bacterial community SYN1, that prevented Cd and Pb uptake in rice through hydroponic experiment. This community lowered Cd levels in the roots and upper roots by 36.
Int J Biol Macromol
January 2025
State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Institute of Applied Ecology, Fujian Agriculture and Forestry University, Fuzhou 350002, China; Joint International Research Laboratory of Ecological Pest Control, Ministry of Education, Fuzhou 350002, China; Ministerial and Provincial Joint Innovation Centre for Safety Production of Cross-Strait Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China; Key Laboratory of Integrated Pest Management for Fujian-Taiwan Crops, Ministry of Agriculture, Fuzhou 350002, China; Key Laboratory of Green Pest Control, Fujian Province University, Fuzhou 350002, China. Electronic address:
The β-tubulin gene is essential for reproductive development, especially for male fertility, in different insects including Bombyx mori and Drosophila melanogaster. Targeting reproductive genes such as β-tubulin offers a promising approach to pest control that is more sustainable than chemical pesticides. However, there is limited research on the functional role of β-tubulin in Plutella xylostella, a highly damaging pest of vegetable crops.
View Article and Find Full Text PDFEnviron Pollut
January 2025
Civil and Construction Engineering and Environmental and Ecological Engineering, Purdue University, 550 Stadium Mall Drive, West Lafayette, Indiana, United States 47907. Electronic address:
This study evaluated microbial fitness under selective pressure of various erythromycin concentrations and the development of resistance genes in Escherichia coli (E. coli) and Enterococcus faecalis (E. faecalis).
View Article and Find Full Text PDFInt Immunopharmacol
January 2025
West China School of Public Health and West China Fourth Hospital, Sichuan University, Chengdu, China. Electronic address:
Cervical cancer is the fourth most common cancer and the fourth leading cause of cancer death in women. Effective treatment of cervical cancer is urgently needed. Tumor therapeutic vaccine is a research hotspot in tumor immunotherapy, and the tumor therapeutic vaccine based on attenuated live bacteria carrier has clinical application prospect because of its clear action site and high safety.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!