Publications by authors named "Li-Chang Cheng"

The selection of appropriate starter cultures is a crucial factor in determining the quality of fermented soymilk products. This study evaluated the effects of a combined starter culture of Enterococcus faecium CGMCC 29309 and Lactiplantibacillus plantarum CGMCC 29306 on the microbiological, physicochemical, textural and rheological characteristics of fermented soymilk. The results indicated that the mixed-strain fermentation significantly increased the concentrations of free isoflavones, free amino acids, free fatty acids, and aroma compound acetaldehyde, 2,3-butanedione and acetoin, and significantly reduced the level of beany compound hexanal.

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To understand the heavy metal pollution status of Dongjiang Lake, the contents and species of heavy metals in the surface sediments were investigated during September 2021, and the heavy metal pollution level and potential ecological risk were evaluated. The results showed that Cd, Pb, As, Cu, Zn, Ni, and Cr contents were in the range of 0.40-34.

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Article Synopsis
  • β--acetylhexosaminidases from the GH20 family are crucial enzymes for modifying oligosaccharides, with significant roles in biology and biotechnology.
  • The study focused on Am2136, a specific β--acetylhexosaminidase from an anaerobic gut bacterium, demonstrating its ability to cleave mucin glycans and highlighting its generalist nature by hydrolyzing β-linkages of various substrates.
  • The research also uncovered that the enzyme's activity is enhanced by nucleotides, suggesting a novel regulatory mechanism linked to structural interactions between enzyme domains, which could facilitate the development of targeted glycan-modifying catalysts.
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  • Akkermansia muciniphila is a significant gut bacterium that helps modulate immune responses and provides nutrients for intestinal health.
  • Research focused on the structure of its sulfatase enzyme, AmAS, revealing key areas that are critical for its function and substrate binding.
  • Understanding the structural differences in these sulfatases could clarify their roles in breaking down complex sugars and their interactions within the human gut.
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Background: Crotonase superfamily members exhibit great catalytic diversity towards various acyl-CoA substrates. A common CoA moiety binding pattern is usually observed in this family, understanding the substrate-binding mechanism would facilitate the rational engineering of crotonases for improved properties.

Methods: We applied X-ray crystallography to investigate a putative enoyl-CoA hydratase/isomerase OdaA in Pseudomonas aeruginosa.

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Colonization factor CFA/I defines the major adhesive fimbriae of enterotoxigenic Escherichia coli and mediates bacterial attachment to host intestinal epithelial cells. The CFA/I fimbria consists of a tip-localized minor adhesive subunit, CfaE, and thousands of copies of the major subunit CfaB polymerized into an ordered helical rod. Biosynthesis of CFA/I fimbriae requires the assistance of the periplasmic chaperone CfaA and outer membrane usher CfaC.

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  • ScPrx1 is a yeast mitochondrial enzyme that protects cells from oxidative stress by utilizing reducing agents like ScTrx3 and glutathione, but its substrate recognition mechanism still needs further investigation.
  • The study determined the structure and oligomeric state of ScPrx1, revealing it exists as a homodimer with specific mutations enhancing or reducing its catalytic activity.
  • The findings suggest that changes in the C-terminal segment and certain loop regions of ScPrx1 are crucial for its catalytic function and its ability to use various reductants.
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Biofilm formation is a critical determinant in the pathopoiesis of It could significantly increase bacterial resistance to drugs and host defense. Thus, inhibition of biofilm matrix production could be regarded as a promising attempt to prevent colonization of and the subsequent infection. PpgL, a periplasmic gluconolactonase, has been reported to be involved in quorum-sensing (QS) system regulation.

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A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

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Gene PA4980 from Pseudomonas aeruginosa encodes a putative enoyl-coenzyme A hydratase/isomerase that is associated with the function of the biofilm dispersion-inducing signal molecule cis-2-decenoic acid. To elucidate the role of PA4980 in cis-2-decenoic acid biosynthesis, we reported the crystal structure of its protein product at 2.39 Å.

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  • * The study identifies key amino acids (Glu126, Glu146, Cys127, Cys131, and Cys154) that are crucial for DspI's function in synthesizing CDA.
  • * Deleting the dspI gene leads to reduced production of pyoverdine, slower movement, impaired biofilm formation, and decreased virulence of P. aeruginosa, suggesting DspI's role in the pathogen’s ability to cause infection.
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In plants and microorganisms, aspartate kinase (AK) catalyzes an initial commitment step of the aspartate family amino acid biosynthesis. Owing to various structural organizations, AKs from different species show tremendous diversity and complex allosteric controls. We report the crystal structure of AK from (PaAK), a typical α2β2 hetero-tetrameric enzyme, in complex with inhibitory effectors.

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  • Pa-PepP is a virulence gene that can be targeted for new anti-drug development, as it plays a key role in pathogenic bacteria's ability to invade hosts.
  • The protein has a unique structure, confirmed to have a specific fold and assemble functionally into a tetramer, with metal ions influencing its activity.
  • Important functional studies revealed a loop crucial for binding large substrates and its non-conserved nature is linked to the bacteria's virulence, which could help in designing targeted inhibitors against infections.
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Background: H7N9 continues to cause human infections and remains a pandemic concern. Understanding the economic impacts of this novel disease is important for making decisions on health resource allocation, including infectious disease prevention and control investment. However, there are limited data on such impacts.

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The effective therapy of fluoride-induced bone diseases requires an understanding of the mechanism of the disorders. Changes in the inhibitors of the Wnt/β-catenin pathway, Dickkopf-1 (Dkk-1) and Sclerostin (SOST),were studied in supernatants harvested from rat skin fibroblasts cultured with varied doses of fluoride. The contents of SOST and Dkk-1 in fibroblast supernatants were assessed at four exposure time-points and investigated by using the method of ELISA.

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LH and FSH have complementary functions in ensuring optimal oocyte maturation and ovulation. In women undergoing assisted reproduction technology protocols with gonadotrophin-releasing hormone analogues, LH and FSH concentrations are reduced. While FSH use in assisted reproduction technology is well established, there is no published consensus on the need for exogenous LH in Asian patients.

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Motivation: Software applications for structural similarity searching and clustering of small molecules play an important role in drug discovery and chemical genomics. Here, we present the first open-source compound mining framework for the popular statistical programming environment R. The integration with a powerful statistical environment maximizes the flexibility, expandability and programmability of the provided analysis functions.

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