Materials Today Bio
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2026
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IF 11
Yue Meng,Chao Miao,Jiaxin Guo,Wei Zhang,Ling Guo,Yu Zhang,Yujun Jiang
Inflammatory bowel disease (IBD) is characterized by elevated levels of reactive oxygen species (ROS) and pro-inflammatory cytokines, alongside disrupted gut microbiota. Therefore, eliminating ROS in the inflammatory site by antioxidant enzymes such as catalase (CAT) and superoxide dismutase (SOD) represents a promising therapeutic strategy for IBD. To this end, we genetically engineered Lactococcus lactis to construct an antioxidant probiotic strain, LL-SC, by integrating a fusion gene (SC) encoding SOD and CAT. To further enhance gastrointestinal survival, LL-SC was encapsulated with a composite nanomaterial of mucosal-adhesive chitosan and sodium alginate to produce LL-SC-C 2 A 2 with antioxidant enzyme expression capability and a nano-protective coating. Compared to uncoated LL-SC, LL-SC-C 2 A 2 exhibited significantly improved gastric acid tolerance with 1.4-fold increases. Protective effects of LL-SC-C 2 A 2 were confirmed across cellular and animal models, including H 2 O 2 -stimulated Caco-2 cells and a DSS-induced murine colitis model. This was achieved through ROS scavenging, pro-inflammatory cytokine reduction, intestinal barrier reinforcement, and restoration of gut microbiota homeostasis. Overall, food-grade LL-SC-C 2 A 2 represents a novel approach to probiotic modification, providing a new strategy and experimental evidence supporting further development for IBD therapy.
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PubMed
高影响因子
FISH & SHELLFISH IMMUNOLOGY
·
2020
·
IF 0
Chen Zhang,Sheng Guo,Zhao Zhao,Zi-Rao Guo,Rui Ma,Gao-Xue Wang,Bin Zhu
Spring viremia of carp virus (SVCV) causes devastating disease in aquaculture, resulting in significant economic impact. To develop an effective means against SVCV infection, a Lactococcus lactis ( L.lactis ) based subunit vaccine (pNZ-UGA) was developed based on surface displaying of SVCV glycoprotein using anchoring motif of the cA (C terminus of the peptidoglyvsn-binding) domains of AcmA, a major autolysin from L.lactis . The surface expression of SVCV glycoprotein was verified by indirect immunofluorescence assay. The efficacy of the constructed vaccine was further evaluated in common carp . The results showed that the higher levels of specific IgM could be detected in fish vaccinated with pNZ-UGA, compared with that in PBS and L.lactis groups. Immune-related genes including TNF-α , IL-6b , IL-1β , Cxcr 1 , Cxca , IFNg2b , I-IFN , and IgM expression in pNZ-UGA group were strongly up-regulated, revealing that robust innate immune response was induced. Notably, the lowest cumulative mortality (13.46%) was observed in fish vaccinated with pNZ-UGA vaccine after SVCV challenge, whereas the cumulative mortality were 100.00% and 92.31% in PBS and L.lactis groups, respectively. This study suggests the potential use of the recombinant L.lactis with surface displaying antigen proteins as effective vaccines against SVCV and other fish virus infection .
研究领域:
水产养殖
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病毒学
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免疫学
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微生物学
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PubMed
JOURNAL OF CHROMATOGRAPHY A
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2022
·
IF 4.601
Jing Jing Peng,Yang Liu,Fu Tian Yu,He Liang Fan,Shi Yang Yue,Yu Hui Fang,Xiao Ling Liu,Cheng-Hua Wang
A reliable method for simultaneous determination of four organic selenium species by HPLC-ICP-MS was developed and implemented in determining organic selenoamino acids (Se-AAs) in selenoproteins from Lactococcus lactis ( L. lactis ) NZ9000. The method consisted of liberating Se-AAs from selenoproteins using ultrasound-assisted protease hydrolysis, and quantitatively detecting Se-AA speciations by HPLC-ICP-MS. After optimizations of proteolysis conditions, chromatographic conditions and determination conditions, the established method could efficiently separate the four Se-AAs, including SeCys, SeCys2, SeMeCys and SeMet within 10 min. It presented high sensitivity with the limits of detection and quantitation in the range of 0.197∼0.240 μg∙L −1 and 0.788∼0.960 μg∙L −1 , respectively, good repeatability with a relative standard deviation (RSD) of less than 5%, and good recovery in the desired floating range of 90%∼105%, verifying the good accuracy. The method successfully detected four selenium species in the purified glutathione peroxidase (LlGPx) overexpressed in L. lactis NZ9000, SeCys (0.9716∼1.6784 μg∙g −1 ), SeCys2 (1.0695∼1.2124 μg∙g −1 ), SeMeCys (0.7288∼0.7984 μg∙g −1 ) and SeMet (1.0058∼1.9571 μg∙g −1 ), accounting for up to 80.14% of total selenium. There was no difference of order of magnitude in the four Se-AAs, indirectly indicating the random incorporation of selenium into selenoprotein LlGPx in L. lactis NZ9000. This work throws new light on the identification and biosynthesis of organic selenium species in selenoproteins and selenium-riched organisms like L. lactis .
研究领域:
分析化学
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生物化学
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微生物学
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PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2024
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IF 5.7
Shengdi Gu,Junjie Yu,Lei Du,Daihui Zhang,Li Zhao,Jingli Xie
PepXLcMY-3, an X-prolyl dipeptidyl aminopeptidase derived from Lactobacillus lactis MY-3, was screened and recombinantly expressed in Escherichia coli. The enzyme could exhibit about 40% activity within the pH range of 6.0–10. To further improve the pH robustness, site E396 located in the active pocket was discovered through alanine scanning. The mutant E396I displayed both developed activity and kcat/Km. The optimal pH of E396I shifted from 6.0 to 10 compared to WT, with the relative activity within the pH range of 6.0–10 significantly increased. The site K648 was then proposed by semirational design. The activity of mutant E396I/K648D reached 4.03 U/mg. The optimal pH was restored to 6.0, and the pH stability was further improved. E396I/K648D could totally hydrolyze β-casomorphin 7 within 30 min. The hydrolysate showed 64.5% inhibition on angiotensin I converting enzyme, which was more efficient than those produced by E396I and WT, 23.2 and 44.7%, respectively.
研究领域:
酶学
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生物技术
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蛋白质工程
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食品科学
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高影响因子
Fishes
·
2026
·Vol. 11
·期 6
·356
·
IF 2.9
Wenhao Ren,Xintong Liu,Kaiyu Yang,Qi Liu,Shuying Ren,Chunyan Zhao,Aihuan Song,Yichao Ren
This study evaluated Lactococcus lactis RDN-1 and its inorganic selenium-enriched derivative in hybrid sturgeon, focusing on growth performance, immune responses, and intestinal health. A 21-day feeding trial was conducted with four groups: control (CK),L. lactisRDN-1 (R), inorganic selenium-enrichedL. lactisRDN-1 (RX), and enrofloxacin (E). All supplemented groups exhibited significantly improved weight gain. The R group attained the highest levels of most essential and total amino acids, whereas the RX group achieved the highest methionine content. In contrast, the E group exhibited significantly lower levels of most amino acids compared to the R and RX groups. The R group suppressed the abundance of Proteobacteria while enriching beneficial genera such asLactococcus, thereby enhancing functional capacities related to energy metabolism, amino acid biosynthesis, and signal transduction. The RX group promoted Firmicutes andBradyrhizobium, and exhibited superior functional characteristics in antioxidant capacity and secondary metabolite biosynthesis. Moreover, the RX group down-regulatedIL-6, demonstrating a balanced immunomodulatory effect with anti-inflammatory potential. In conclusion,L. lactisRDN-1 and its selenium-enriched derivative represent promising antibiotic alternatives.L. lactisRDN-1 alone offers more comprehensive effects, whereas inorganic selenium supplementation partially impairs its overall performance but achieves more accurate immune regulation. This work provides a scientific foundation for the precise application ofL. lactis.
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高影响因子
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