INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2025
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IF 8.5
Jingjing Shen,Long Zheng,Guangning Chen,Achiraya Khamleng,Changhu Xue,Yaoguang Chang
Sulfated fucan, an important marine polysaccharide frequently presented in echinoderms and brown algae, has gained growing attention owing to its various biological activities. Fucanases are essential tools for degrading sulfated fucan to produce corresponding oligosaccharides. In this context, an endo-1,3-fucanase (Fun187Al) belonging to the GH187 family was successfully expressed in Escherichia coli . Fun187Al showed the highest activity at 30–40 °C and pH 7.5. It hydrolyzed sulfated fucan in a random endo -acting pattern, and displayed a substrate specificity different from the endo-1,3-fucanases of other glycoside hydrolase family. Analyses of ultra-performance liquid chromatography coupled with high-resolution mass spectrometry revealed that tetrasaccharide with two sulfate groups (Fuc 4 S 2 ), Fuc 4 S 3 , and Fuc 4 S 4 were respectively the major components in the end products of Fun187Al against sulfated fucans from Acaudina molpadioides , Thelonota ananas , and Holothuria tubulosa . The capability of Fun187Al to produce oligosaccharides with different degrees of polymerization and sulfation patterns demonstrated that it could be regarded as a favorable tool for establishing the structure-activity relationships of sulfated fucan and its oligosaccharides.
研究领域:
生物化学
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海洋生物学
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分子生物学
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产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2025
·
IF 8.5
Chuying Huo,Xueting Zhang,Quanwei Zhang,Jing Li,Wenting Zhao,Simin Qi,Hauyee Fung,Wei Yang,Xi Shi,Huiyuan Cheng,Hubiao Chen,Joshua Kashun Ko,Karl Wahkeung Tsim,Hiuyee Kwan,Lifeng Li,Quanbin Han
While Dendrobii β-1,4-mannan (DOP) shows promise in treating colitis, previous research only correlated changes in gut microbiota composition with DOP's effects, without elucidating the specific mechanism by which gut microbiota mediates DOP's bioactivities. This study addresses this crucial gap by demonstrating the essential role of vancomycin-sensitive gut bacteria in mediating the anti-colitis effects of DOP. Using targeted antibiotic perturbation, we found that vancomycin, but not neomycin, abolished both DOP degradation and its therapeutic effects in colitis mice. This loss of efficacy was attributed to the depletion of mannan endo-1,4-β-mannosidase (EC 3.2.1.78), a verified enzyme for DOP catabolism. The expression of this enzyme was increased in DOP-treated microbiota, together with a stronger catalytic ability in DOP degradation. We further identified Bifidobacterium pseudolongum , a vancomycin-sensitive species, as an important contributor to DOP fermentation and its anti-colitis effects. This bacterium initiates DOP's degradation by cleaving it into bioactive mannan oligosaccharides. In summary, this research reveals that the breakdown of DOP by mannan endo-1,4-β-mannosidase in vancomycin-sensitive B. pseudolongum plays a significant role in its anti-colitis effects. This work advances the field by demonstrating that vancomycin-sensitive bacteria, such as B. pseudolongum , mediate DOP's efficacy and establishing polysaccharide catabolism as critical for its therapeutic activity.
研究领域:
微生物学
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胃肠病学
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免疫学
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分子生物学
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营养科学
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DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2016
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IF 2.857
Chun Liu,Fenfen Cheng,Yingen Sun,Hongyu Ma,Xiaoquan Yang
An alkaline isoform of the PR-5 protein (designated GmOLPc) has been purified from soybean hulls and identified by MALDI-TOF/TOF-MS. GmOLPc effectively inhibited in vitro the growth of Phytophthora soja spore and Pseudomonas syringae pv glycinea. The antimicrobial activity of GmOLPc should be mainly ascribed to its high binding affinity with vesicles composed of DPPG, (1,3)-β-d-glucans, and weak endo-(1,3)-β-d-glucanase activity. From the 3D models, predicted by the homology modeling, GmOLPc contains an extended negatively charged cleft. The cleft was proved to be a prerequisite for endo-(1,3)-β-d-glucanase activity. Molecular docking revealed that the positioning of linear (1,3)-β-d-glucans in the cleft of GmOLPc allowed an interaction with Glu83 and Asp101 that were responsible for the hydrolytic cleavage of glucans. Interactions of GmOLPc with model membranes indicated that GmOLPc possesses good surface activity which could contribute to its antimicrobial activity, as proved by the behavior of perturbing the integrity of membranes through surface hydrophobic amino acid residues (Phe89 and Phe94).
研究领域:
植物病理学
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分子生物学
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生物化学
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产品关联
DOI
PubMed
高影响因子
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