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  1. Article ; Online: Retraction for Ni et al., "Autoregulation of Lantibiotic Bovicin HJ50 Biosynthesis by the BovK-BovR Two-Component Signal Transduction System in

    Ni, Jianqiang / Teng, Kunling / Liu, Gang / Qiao, Caixia / Huan, Liandong / Zhong, Jin

    Applied and environmental microbiology

    2024  Volume 90, Issue 3, Page(s) e0000624

    Language English
    Publishing date 2024-02-26
    Publishing country United States
    Document type Retraction of Publication
    ZDB-ID 223011-2
    ISSN 1098-5336 ; 0099-2240
    ISSN (online) 1098-5336
    ISSN 0099-2240
    DOI 10.1128/aem.00006-24
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Dissection of the bridging pattern of bovicin HJ50, a lantibiotic containing a characteristic disulfide bridge.

    Lin, Yuheng / Teng, Kunling / Huan, Liandong / Zhong, Jin

    Microbiological research

    2011  Volume 166, Issue 3, Page(s) 146–154

    Abstract: Bovicin HJ50, a lantibiotic produced by Streptococcus bovis HJ50, is featured by the presence of a disulfide bridge. This study described a simplified in vitro synthetic strategy for producing bovicin HJ50 totally based on Escherichia coli expression ... ...

    Abstract Bovicin HJ50, a lantibiotic produced by Streptococcus bovis HJ50, is featured by the presence of a disulfide bridge. This study described a simplified in vitro synthetic strategy for producing bovicin HJ50 totally based on Escherichia coli expression system. In this strategy termed as Semi-in vitro biosynthesis (SIVB), prepeptide BovA and modification enzyme BovM were co-expressed to generate posttranslationally modified BovA. Then a specific protease BovT150 was employed to remove the leader peptide in vitro and produce biologically active bovicin HJ50. Via SIVB, a series of ring-broken bovicin mutants C13A, C21A, C29A and T10A/C32A were prepared by introducing site-directed mutations into bovA gene. Further, we analyzed the bridging patterns of these mutants through chemical modification and successfully clarified the bridging pattern of bovicin HJ50. The results showed that two thioether bridges exist between Thr8 and Cys13, and Thr10 and Cys32, respectively, and that the disulfide bond bridging Cys21 and 29 is very relevant for the antimicrobial activity of bovicin HJ50. This is the first study that reports the bridging pattern of bovicin HJ50.
    MeSH term(s) Bacteriocins/biosynthesis ; Bacteriocins/chemistry ; Bacteriocins/metabolism ; Disulfides/chemistry ; Escherichia coli/genetics ; Escherichia coli/metabolism ; Gene Expression ; Mutagenesis, Site-Directed ; Protein Processing, Post-Translational ; Streptococcus bovis/metabolism ; Sulfides
    Chemical Substances Bacteriocins ; Disulfides ; Sulfides
    Language English
    Publishing date 2011-03-20
    Publishing country Germany
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1189614-0
    ISSN 1618-0623 ; 0944-5013
    ISSN (online) 1618-0623
    ISSN 0944-5013
    DOI 10.1016/j.micres.2010.05.001
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Expression of hepatitis B virus surface antigen determinants in Lactococcus lactis for oral vaccination.

    Zhang, Qiuxiang / Zhong, Jin / Huan, Liandong

    Microbiological research

    2011  Volume 166, Issue 2, Page(s) 111–120

    Abstract: Lactococcus lactis with non-pathogenic and non-colonizing properties is an attractive candidate for delivering biologically active proteins by mucosal routes. In this report we described recombinant L. lactis applicable for the development of live ... ...

    Abstract Lactococcus lactis with non-pathogenic and non-colonizing properties is an attractive candidate for delivering biologically active proteins by mucosal routes. In this report we described recombinant L. lactis applicable for the development of live mucosal vaccine against hepatitis B virus (HBV). The PreS region of the HBV surface antigen alone or combined with "a" determinant of S region (PreSa) was cloned and expressed in the food grade bacterium L. lactis using a nisin-controlled expression (NICE) system. Western blot analysis indicated that both PreS and PreSa fusion proteins were successfully expressed in L. lactis after nisin induction. Oral immunization of BALB/c mice with PreS and PreSa-producing strains induced both mucosal (intestinal IgA) and systemic (serum IgG) immune responses against HBV at the same magnitude. Two additional groups of mice given L. lactis expressing human interferon-alpha 2b as an adjuvant with the PreS or PreSa-producing strains produced higher IgG but not IgA antibody responses. These results indicated that the lactococci-derived vaccines could be promising candidates as alternative HBV vaccines for preventing hepatitis B.
    MeSH term(s) Adjuvants, Immunologic ; Administration, Oral ; Animals ; Escherichia coli/genetics ; Female ; Hepatitis B Antibodies/blood ; Hepatitis B Surface Antigens/genetics ; Hepatitis B Surface Antigens/immunology ; Hepatitis B Vaccines/administration & dosage ; Hepatitis B Vaccines/immunology ; Humans ; Immunoglobulin A/blood ; Immunoglobulin G/blood ; Interferon-alpha/immunology ; Interferon-alpha/secretion ; Lactococcus lactis/genetics ; Mice ; Mice, Inbred BALB C ; Protein Precursors/genetics ; Protein Precursors/immunology ; Random Allocation ; Recombinant Proteins ; Vaccines, Synthetic/administration & dosage ; Vaccines, Synthetic/immunology
    Chemical Substances Adjuvants, Immunologic ; Hepatitis B Antibodies ; Hepatitis B Surface Antigens ; Hepatitis B Vaccines ; Immunoglobulin A ; Immunoglobulin G ; Interferon-alpha ; Protein Precursors ; Recombinant Proteins ; Vaccines, Synthetic ; presurface protein 2, hepatitis B surface antigen ; interferon alfa-2b (43K1W2T1M6)
    Language English
    Publishing date 2011-02-20
    Publishing country Germany
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1189614-0
    ISSN 1618-0623 ; 0944-5013
    ISSN (online) 1618-0623
    ISSN 0944-5013
    DOI 10.1016/j.micres.2010.02.002
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: Roles of S3 Site Residues of Nattokinase on its Activity and Substrate Specificity

    Wu, Shuming / Feng, Chi / Zhong, Jin / Huan, Liandong

    Journal of biochemistry. 2007 Sept., v. 142, no. 3

    2007  

    Abstract: Nattokinase (Subtilisin NAT, NK) is a bacterial serine protease with high fibrinolytic activity. To probe their roles on protease activity and substrate specificity, three residues of S3 site (Gly¹⁰⁰, Ser¹⁰¹ and Leu¹²⁶) were mutated by site-directed ... ...

    Abstract Nattokinase (Subtilisin NAT, NK) is a bacterial serine protease with high fibrinolytic activity. To probe their roles on protease activity and substrate specificity, three residues of S3 site (Gly¹⁰⁰, Ser¹⁰¹ and Leu¹²⁶) were mutated by site-directed mutagenesis. Kinetics parameters of 20 mutants were measured using tetrapeptides as substrates, and their fibrinolytic activities were determined by fibrin plate method. Results of mutation analysis showed that Gly¹⁰⁰ and Ser¹⁰¹ had reverse steric and electrostatic effects. Residues with bulky or positively charged side chains at position 100 decreased the substrate binding and catalytic activity drastically, while residues with the same characters at position 101 could obviously enhance protease and fibrinolytic activity of NK. Mutation of Leu¹²⁶ might impair the structure of the active cleft and drastically decreased the activity of NK. Kinetics studies of the mutants showed that S3 residues were crucial to keep protease activity while they moderately affected substrate specificity of NK. The present study provided some original insight into the P3-S3 interaction in NK and other subtilisins, as well as showed successful protein engineering cases to improve NK as a potential therapeutic agent.
    Language English
    Dates of publication 2007-09
    Size p. 357-364.
    Publishing place Japanese Biochemical Society
    Document type Article
    ZDB-ID 218073-x
    ISSN 1756-2651 ; 0021-924X
    ISSN (online) 1756-2651
    ISSN 0021-924X
    Database NAL-Catalogue (AGRICOLA)

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  5. Article: Secretory expression of a heterologous nattokinase in Lactococcus lactis

    Liang, Xiaobo / Zhang, Lixin / Zhong, Jin / Huan, Liandong

    Applied microbiology and biotechnology. 2007 May, v. 75, no. 1

    2007  

    Abstract: Nattokinase has been reported as an oral health product for the prevention of atherosclerosis. We developed a novel strategy to express a nattokinase from Bacillus subtilis in a live delivery vehicle, Lactococcus lactis. Promoter P nisZ and signal ... ...

    Abstract Nattokinase has been reported as an oral health product for the prevention of atherosclerosis. We developed a novel strategy to express a nattokinase from Bacillus subtilis in a live delivery vehicle, Lactococcus lactis. Promoter P nisZ and signal peptide SPUsp were used for inducible and secretory expression of nattokinase in L. lactis. Western blotting analysis demonstrated that nattokinase was successfully expressed, and about 94% of the enzyme was secreted to the culture. The recombinant nattokinase showed potent fibrinolytic activity, equivalent to 41.7 urokinase units per milliliter culture. Expression and delivery of such a fibrinolytic enzyme in the food-grade vehicle L. lactis would facilitate the widespread application of nattokinase in the control and prevention of thrombosis diseases.
    Keywords Bacillus subtilis ; Lactococcus lactis ; Western blotting ; atherosclerosis ; signal peptide ; thrombosis ; u-plasminogen activator
    Language English
    Dates of publication 2007-05
    Size p. 95-101.
    Publisher Springer-Verlag
    Publishing place Berlin/Heidelberg
    Document type Article
    ZDB-ID 392453-1
    ISSN 1432-0614 ; 0171-1741 ; 0175-7598
    ISSN (online) 1432-0614
    ISSN 0171-1741 ; 0175-7598
    DOI 10.1007/s00253-006-0809-4
    Database NAL-Catalogue (AGRICOLA)

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  6. Article: [Advances in the study of nisin resistance--a review].

    Chu, Xiaodong / Lin, Yuheng / Sun, Zhizeng / Huan, Liandong / Zhong, Jin

    Wei sheng wu xue bao = Acta microbiologica Sinica

    2010  Volume 50, Issue 9, Page(s) 1129–1134

    Abstract: Nisin, a lantibiotic produced by some species of Lactococcus lactis, has broad antibacterial spectrum against Gram-positive bacteria species, especially those with close phylogenetic relationship to the nisin producing strain. The broad use of nisin did ... ...

    Abstract Nisin, a lantibiotic produced by some species of Lactococcus lactis, has broad antibacterial spectrum against Gram-positive bacteria species, especially those with close phylogenetic relationship to the nisin producing strain. The broad use of nisin did not lead to widespread resistance. However, some non-nisin producing bacteria could develop certain mechanisms of resistance against nisin when growing under laboratory or nature selection pressure. Nisin resistance mainly involved two strategies, namely, the non-specific physiological isolation mechanism (by the change of cell wall or membrane structure and composition) and the specific protease-mediated mechanism. This review introduced the advances in the study of nisin resistance mechanism.
    MeSH term(s) Anti-Bacterial Agents/pharmacology ; Bacteria/cytology ; Bacteria/drug effects ; Bacteria/metabolism ; Drug Resistance, Bacterial/physiology ; Nisin/pharmacology
    Chemical Substances Anti-Bacterial Agents ; Nisin (1414-45-5)
    Language Chinese
    Publishing date 2010-09
    Publishing country China
    Document type English Abstract ; Journal Article ; Research Support, Non-U.S. Gov't ; Review
    ZDB-ID 412683-x
    ISSN 0001-6209 ; 0098-9150
    ISSN 0001-6209 ; 0098-9150
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: [Improving heat and pH stability of nisin by site-directed mutagenesis].

    Lu, Yao / Jiang, Like / Chen, Meiling / Huan, Liandong / Zhong, Jin

    Wei sheng wu xue bao = Acta microbiologica Sinica

    2010  Volume 50, Issue 11, Page(s) 1481–1487

    Abstract: Objective: The aim of this study was to optimize the property of nisin through altering its specific amino acid by site-directed mutagenesis method.: Methods: On the basis of M21K nisinZ, a former reported nisinZ mutant that exhibited antimicrobial ... ...

    Abstract Objective: The aim of this study was to optimize the property of nisin through altering its specific amino acid by site-directed mutagenesis method.
    Methods: On the basis of M21K nisinZ, a former reported nisinZ mutant that exhibited antimicrobial activity against Gram-negative bacteria, the 29th amino acid of it was mutated from serine to lysine. The mutant M21K/S29K nisZ gene was cloned into vector pMG36e and the recombinant plasmid was introduced into Lacotococcus lactis NZ9800. The resulting M21K/S29K nisinZ was then isolated and purified, and its antibacterial activity, antibacterial spectrum and stability were analyzed and compared to those of M21K nisinZ and nisinZ.
    Results: Compared with wild-type nisinZ and M21K nisinZ, the M21K/S29K nisinZ displayed reduced antimicrobial activity, but showed significantly increased stabilities to heat and pH stress. Moreover, M21K/S29K nisinZ also exhibited antimicrobial activity against Gram-negative bacteria as M21K nisinZ did.
    Conclusion: By changing the 29th amino acid of nisin, we can optimize the property of nisin, especially its stability to heat and pH stress.
    MeSH term(s) Anti-Bacterial Agents/chemistry ; Anti-Bacterial Agents/isolation & purification ; Anti-Bacterial Agents/metabolism ; Bacteria/chemistry ; Bacteria/genetics ; Bacteria/metabolism ; Genetic Engineering ; Hot Temperature ; Hydrogen-Ion Concentration ; Mutagenesis, Site-Directed ; Nisin/chemistry ; Nisin/genetics ; Nisin/isolation & purification ; Nisin/metabolism
    Chemical Substances Anti-Bacterial Agents ; Nisin (1414-45-5)
    Language Chinese
    Publishing date 2010-11
    Publishing country China
    Document type English Abstract ; Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 412683-x
    ISSN 0001-6209 ; 0098-9150
    ISSN 0001-6209 ; 0098-9150
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article: [Enhanced nisin production by overexpression of nisin immunity gene nisI in the nisin-producing strain].

    Hu, Hongmei / Jiang, Like / Lin, Yuheng / Huan, Liandong / Zhong, Jin

    Wei sheng wu xue bao = Acta microbiologica Sinica

    2010  Volume 50, Issue 10, Page(s) 1341–1346

    Abstract: Objective: Our aim was to enhance nisin production by overexpression of nisin immunity gene nisI in nisin-producing strains.: Methods: Nisin immunity gene nisI with a strong promoter P59 was cloned into vector pHJ201 and introduced into Lacotococcus ... ...

    Abstract Objective: Our aim was to enhance nisin production by overexpression of nisin immunity gene nisI in nisin-producing strains.
    Methods: Nisin immunity gene nisI with a strong promoter P59 was cloned into vector pHJ201 and introduced into Lacotococcus lactis NZ9800, resulting in a recombinant strain L. lactis NZ9800/pHMI. Then the differences between the recombinant strain and the control strain L. lactis NZ9800/pHJ201 were analyzed in several aspects, including their growth curves, nisin resistance level and antibacterial activity against indicator strain Microccus flavus NCIB 8166.
    Results: The overexpression of nisI had no significant difference in growth rate between recombinant strain and contrast strain. However, it promoted recombinant strain tolerance 25% higer nisin resistance level and stronger antibacterial activity against M. flavus NCIB 8166, which was increased by 32% and 25% when fermented for 6 and 8 hours, respectively.
    Conclusion: These results indicated that overexpression of nisI gene in the nisin producing strain can effectively enhance nisin resistence level and thus improve nisin production.
    MeSH term(s) Anti-Bacterial Agents/biosynthesis ; Anti-Bacterial Agents/pharmacology ; Gene Expression Regulation, Bacterial/drug effects ; Gene Expression Regulation, Bacterial/immunology ; Immunity/drug effects ; Lactococcus lactis/genetics ; Lactococcus lactis/immunology ; Lactococcus lactis/metabolism ; Nisin/biosynthesis ; Nisin/pharmacology ; Operon ; Promoter Regions, Genetic/drug effects ; Promoter Regions, Genetic/genetics ; Transcription, Genetic
    Chemical Substances Anti-Bacterial Agents ; Nisin (1414-45-5)
    Language Chinese
    Publishing date 2010-10
    Publishing country China
    Document type English Abstract ; Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 412683-x
    ISSN 0001-6209 ; 0098-9150
    ISSN 0001-6209 ; 0098-9150
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Improvement of human interferon alpha secretion by Lactococcus lactis.

    Zhang, Qiuxiang / Zhong, Jin / Liang, Xiaobo / Liu, Wenjun / Huan, Liandong

    Biotechnology letters

    2010  Volume 32, Issue 9, Page(s) 1271–1277

    Abstract: To improve the secretion and expression of human interferon alpha 2b (IFN) in Lactococcus lactis, a synthetic pro-peptide, LEISSTCDA (LEISS), was fused to the N-terminus of IFN. This gave a higher secretion efficiency (12% vs. 5%) and yield ( ... ...

    Abstract To improve the secretion and expression of human interferon alpha 2b (IFN) in Lactococcus lactis, a synthetic pro-peptide, LEISSTCDA (LEISS), was fused to the N-terminus of IFN. This gave a higher secretion efficiency (12% vs. 5%) and yield (approximately 2.8-fold) of IFN. The signal peptide, SP(SlpA) (SlpA, an S-layer protein of Lactobacillus brevis), was also tested to secrete IFN instead of SP(Usp45) (Usp45, the main secreted protein in L. lactis). This gave increased IFN secretion (approximately 3-fold) but lower total production. All the recombinant IFN had appropriate bioactivities in an antiviral assay.
    MeSH term(s) Antiviral Agents/pharmacology ; Bacterial Proteins/genetics ; Gene Expression ; Humans ; Interferon-alpha/genetics ; Interferon-alpha/secretion ; Lactobacillus brevis/genetics ; Lactococcus lactis/genetics ; Lactococcus lactis/metabolism ; Neutralization Tests ; Protein Sorting Signals ; Recombinant Fusion Proteins/genetics ; Recombinant Fusion Proteins/secretion ; Recombinant Proteins ; Vesiculovirus/drug effects
    Chemical Substances Antiviral Agents ; Bacterial Proteins ; Interferon-alpha ; Protein Sorting Signals ; Recombinant Fusion Proteins ; Recombinant Proteins ; surface layer protein A, Bacteria ; interferon alfa-2b (43K1W2T1M6)
    Language English
    Publishing date 2010-09
    Publishing country Netherlands
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 423853-9
    ISSN 1573-6776 ; 0141-5492
    ISSN (online) 1573-6776
    ISSN 0141-5492
    DOI 10.1007/s10529-010-0285-x
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Adverse effect of nisin resistance protein on nisin-induced expression system in Lactococcus lactis.

    Liang, Xiaobo / Sun, Zhizeng / Zhong, Jin / Zhang, Qiuxiang / Huan, Liandong

    Microbiological research

    2010  Volume 165, Issue 6, Page(s) 458–465

    Abstract: Nisin is a bacteriocin that is widely used as a safe, natural preservative in food products. Nisin-controlled gene expression (NICE) systems and food-grade expression systems with nisin resistance as the selection marker are increasingly attracting ... ...

    Abstract Nisin is a bacteriocin that is widely used as a safe, natural preservative in food products. Nisin-controlled gene expression (NICE) systems and food-grade expression systems with nisin resistance as the selection marker are increasingly attracting attention owing to their food-grade statuses. However, the putative influence of nisin resistance on NICE systems deserves consideration when nisin is used as both the inducer and selection agent in lactococcal strains. In this paper, we described the cloning of the nisin resistance gene (nsr) and studied the effect of the encoded nisin resistance protein (NSR) on the efficiency of the NICE system in Lactococcus lactis, with the green fluorescence protein as the reporter protein. Results showed that NSR expression significantly weakened the inducing activity of nisin. Further studies have confirmed that this reduction in the inducing activity of nisin was a consequence of the proteolytic activity of NSR against nisin; the digested products showed drastically decreased inducing activities than native nisin. Conclusively, the expression of NSR imposes an adverse effect on the NICE system in L. lactis.
    MeSH term(s) Bacterial Proteins/adverse effects ; Bacterial Proteins/genetics ; Bacterial Proteins/metabolism ; Cloning, Molecular ; Drug Resistance, Bacterial ; Gene Expression Regulation, Bacterial/drug effects ; Lactococcus lactis/drug effects ; Lactococcus lactis/genetics ; Lactococcus lactis/metabolism ; Molecular Sequence Data ; Nisin/adverse effects ; Nisin/pharmacology
    Chemical Substances Bacterial Proteins ; Nisin (1414-45-5)
    Language English
    Publishing date 2010-08-20
    Publishing country Germany
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1189614-0
    ISSN 1618-0623 ; 0944-5013
    ISSN (online) 1618-0623
    ISSN 0944-5013
    DOI 10.1016/j.micres.2009.10.001
    Database MEDical Literature Analysis and Retrieval System OnLINE

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