Bacterial UDP-glucose dehydrogenase (UDPGlcDH) is essential for formation of the antiphagocytic capsule that protects many virulent bacteria such as Streptococcus pyogenes andStreptococcus pneumoniae type 3 from the host's immune system. We have determined the X-ray structures of both native and Cys260Ser UDPGlcDH from S. pyogenes (74% similarity to S. pneumoniae) in ternary complexes with UDP-xylose/NAD(+) and UDP-glucuronic acid/NAD(H), respectively. The 402 residue homodimeric UDPGlcDH is composed of an N-terminal NAD(+) dinucleotide binding domain and a C-terminal UDP-sugar binding domain connected by a long (48 A) central alpha-helix. The first 290 residues of UDPGlcDH share structural homology with 6-phosphogluconate dehydrogenase, including conservation of an active site lysine and asparagine that are implicated in the enzyme mechanism. Also proposed to participate in the catalytic mechanism are a threonine and a glutamate that hydrogen bond to a conserved active site water molecule suitably positioned for general acid/base catalysis.
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J Environ Manage
January 2025
Key Laboratory of Marine Environment and Ecology, Ministry of Education, Ocean University of China, Qingdao, 266100, China; College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China.
Invest Ophthalmol Vis Sci
January 2025
State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China.
Purpose: Eyelid infiltrative basal cell carcinoma (iBCC) is the most common malignant tumor affecting the ocular adnexa, but studies on metabolic changes within its microenvironment and heterogeneity at the tumor invasive area are limited. This study aims to analyze metabolic differences among iBCC cell types using single-cell and spatial metabolomics analysis and to examine metabolic environment at the tumor invasive area.
Methods: Single-cell transcriptomic data of human basal cell carcinoma (BCC) were clustered and visualized using Uniform Manifold Approximation and Projection.
Biochemistry
January 2025
Department of Biochemistry & Molecular Biology, University of Georgia, Athens, Georgia 30602, United States.
Human UDP-glucose dehydrogenase (hUGDH) catalyzes the oxidation of UDP-glucose into UDP-glucuronic acid, an essential substrate in the Phase II metabolism of drugs. hUGDH is a hexamer that exists in an equilibrium between an active (E) state and an inactive (E) state, with the latter being stabilized by the binding of the allosteric inhibitor UDP-xylose (UDP-Xyl). The allosteric transition between E and E is slow and can be observed as a lag in progress curves.
View Article and Find Full Text PDFMetab Eng
January 2025
Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China; National Center of Technology Innovation for Synthetic Biology, Tianjin, China; Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China. Electronic address:
Bioresour Technol
January 2025
Graduate Program of Chemical Engineering, Federal University of São Carlos, 13565-905, São Carlos, SP, Brazil. Electronic address:
Current efforts to improve xanthan gum (XG) production by Xanthomonas have focused on the growth medium, operating parameters, and downstream steps. However, a key aspect is the development of optimal strains. The present work aimed to investigate the formation of XG monomers, using kinetic and stoichiometric models to identify possible bottlenecks, and to engineer a recombinant strain to overcome such limitations.
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