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Summer K, Liu L, Guo Q, Barkla B, Benkendorff K. Semi-purified Antimicrobial Proteins from Oyster Hemolymph Inhibit Pneumococcal Infection. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2024:10.1007/s10126-024-10297-w. [PMID: 38430292 DOI: 10.1007/s10126-024-10297-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 02/05/2024] [Indexed: 03/03/2024]
Abstract
Pneumococcal infections caused by Streptococcus pneumoniae are a leading cause of morbidity and mortality globally, particularly among children. The ability of S. pneumoniae to form enduring biofilms makes treatment inherently difficult, and options are further limited by emerging antibiotic resistance. The discovery of new antibiotics, particularly those with antibiofilm activity, is therefore increasingly important. Antimicrobial proteins and peptides (AMPs) from marine invertebrates are recognised as promising pharmacological leads. This study determined the in vitro antibacterial activity of hemolymph and unique protein fractions from an Australian oyster (Saccostrea glomerata) against multi-drug-resistant S. pneumoniae. We developed a successful method for hemolymph extraction and separation into 16 fractions by preparative HPLC. The strongest activity was observed in fraction 7: at 42 µg/mL protein, this fraction was bactericidal to S. pneumoniae and inhibited biofilm formation. Proteomic analysis showed that fraction 7 contained relatively high abundance of carbonic anhydrase, cofilin, cystatin B-like, and gelsolin-like proteins, while surrounding fractions, which showed lower or no antibacterial activity, contained these proteins in lower abundance or not at all. This work supports traditional medicinal uses of oysters and contributes to further research and development of novel hemolymph/AMP-based treatments for pneumococcal infections.
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Affiliation(s)
- Kate Summer
- Faculty of Science and Engineering, Southern Cross University, Military Road, Lismore, NSW, 2480, Australia.
| | - Lei Liu
- Faculty of Science and Engineering, Southern Cross University, Military Road, Lismore, NSW, 2480, Australia
| | - Qi Guo
- Faculty of Science and Engineering, Southern Cross University, Military Road, Lismore, NSW, 2480, Australia
| | - Bronwyn Barkla
- Faculty of Science and Engineering, Southern Cross University, Military Road, Lismore, NSW, 2480, Australia
| | - Kirsten Benkendorff
- National Marine Science Centre, Southern Cross University, 2 Bay Drive, Coffs Harbour, NSW, 2450, Australia
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2
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Innate Immunity Mechanisms in Marine Multicellular Organisms. Mar Drugs 2022; 20:md20090549. [PMID: 36135738 PMCID: PMC9505182 DOI: 10.3390/md20090549] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 08/19/2022] [Accepted: 08/22/2022] [Indexed: 11/27/2022] Open
Abstract
The innate immune system provides an adequate response to stress factors and pathogens through pattern recognition receptors (PRRs), located on the surface of cell membranes and in the cytoplasm. Generally, the structures of PRRs are formed by several domains that are evolutionarily conserved, with a fairly high degree of homology in representatives of different species. The orthologs of TLRs, NLRs, RLRs and CLRs are widely represented, not only in marine chordates, but also in invertebrates. Study of the interactions of the most ancient marine multicellular organisms with microorganisms gives us an idea of the evolution of molecular mechanisms of protection against pathogens and reveals new functions of already known proteins in ensuring the body’s homeostasis. The review discusses innate immunity mechanisms of protection of marine invertebrate organisms against infections, using the examples of ancient multicellular hydroids, tunicates, echinoderms, and marine worms in the context of searching for analogies with vertebrate innate immunity. Due to the fact that mucous membranes first arose in marine invertebrates that have existed for several hundred million years, study of their innate immune system is both of fundamental importance in terms of understanding molecular mechanisms of host defense, and of practical application, including the search of new antimicrobial agents for subsequent use in medicine, veterinary and biotechnology.
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Zhang M, Gao ZC, Chi Z, Wang Z, Liu GL, Li XF, Hu Z, Chi ZM. Massoia Lactone Displays Strong Antifungal Property Against Many Crop Pathogens and Its Potential Application. MICROBIAL ECOLOGY 2022; 84:376-390. [PMID: 34596710 DOI: 10.1007/s00248-021-01885-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 09/24/2021] [Indexed: 06/13/2023]
Abstract
Massoia lactone could be released from liamocins produced by Aureobasidium melanogenum M39. The obtained Massoia lactone was very stable and highly active against many fungal crop pathogens which cause many plant diseases and food unsafety. Massoia lactone treatment not only could effectively inhibit their hyphal growth and spore germination, but also caused pore formation in cell membrane, reduction of ergosterol content, rise in intracellular ROS levels, and leakage of intracellular components, consequently leading to cellular necrosis and cell death. The direct contact of Massoia lactone with Fusarium graminearum spores could stop the development of Fusarium head blight symptom in the diseased wheats. Therefore, Massoia lactone could be a promising candidate for development as an effective and green bio-fungicide because of its high anti-fungal activity and the multiplicity of mode of its action.
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Affiliation(s)
- Mei Zhang
- College of Marine Life Science, Ocean University of China, Yushan Road, No. 5, Qingdao, China
| | - Zhi-Chao Gao
- College of Marine Life Science, Ocean University of China, Yushan Road, No. 5, Qingdao, China
| | - Zhe Chi
- College of Marine Life Science, Ocean University of China, Yushan Road, No. 5, Qingdao, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266003, China
| | - Zhu Wang
- College of Marine Life Science, Ocean University of China, Yushan Road, No. 5, Qingdao, China
| | - Guang-Lei Liu
- College of Marine Life Science, Ocean University of China, Yushan Road, No. 5, Qingdao, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266003, China
| | - Xue-Feng Li
- State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Agronomy, Shandong Agriculture University, Tai'an, 271018, China
| | - Zhong Hu
- Department of Biology, Shantou University, Shantou, 515063, China
| | - Zhen-Ming Chi
- College of Marine Life Science, Ocean University of China, Yushan Road, No. 5, Qingdao, China.
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266003, China.
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Liamocin overproduction by the mutants of Aureobasidium melanogenum 9-1 for effectively killing spores of the pathogenic fungi from diseased human skin by Massoia lactone. World J Microbiol Biotechnol 2022; 38:107. [PMID: 35507122 DOI: 10.1007/s11274-022-03290-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Accepted: 04/14/2022] [Indexed: 10/18/2022]
Abstract
Liamocins and Massoia lactone have many applications. In this study, the glucose-derepressed mutant Δcrea5 in which the CREA gene was removed could produce 36.5 g/L of liamocins. Furthermore, overexpression of the MSN2 gene in the mutant Δcrea5 made the transformant M60 produce 41.4 g/L of liamocins and further overexpression of the GAL1 gene in the transformant M60 rendered the transformant G40 to produce 49.5 ± 0.4 g/L of liamocins during the 10-L fermentation while their wild type strain 9-1 made only 26.3 g/L of liamocins. The expressed transcription activators Msn2 and Gal1 were localized in the nuclei, promoting expression of the genes responsible for liamocins biosynthesis and sugar transport. Massoia lactone prepared from the produced liamocins could actively kill the spores of the pathogenic fungi from the diseased human skin by inhibiting spore germination and causing cellular necrosis of the fungal spores.
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Recombinant human β-defensin130 inhibited the growth of foodborne bacteria through membrane disruption and exerted anti-inflammatory activity. Food Sci Biotechnol 2022; 31:893-904. [PMID: 35720462 PMCID: PMC9203618 DOI: 10.1007/s10068-022-01087-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 04/07/2022] [Accepted: 04/10/2022] [Indexed: 11/04/2022] Open
Abstract
Foodborne pathogens causing food poisoning and infections are detrimental to human health, and the abuse of antibiotics induced severe antibiotic resistance in past decades. Thus, it is urgent to develop new antimicrobial agents. In the current study, human β-defensin 130 (hBD130), which is an antimicrobial peptide identified in human macrophages in 2017, was initially produced in Pichia pastoris. The purified hBD130 demonstrated broad bactericidal spectrum against foodborne pathogens through a membrane disruption, with concentrations ranging from 10 to 45 μg/mL. Moreover, hBD130 showed a low hemolytic effect and nearly no cytotoxicity to mammalian cells with a dosage of 400 μg/mL. In addition, the secretion amounts and mRNA levels of NO, IL-6, IL-1β, and TNF-α in LPS-induced mouse macrophage were significantly decreased with 1 mg/mL of hBD130. Taken together, these results showed that hBD130 is a promising antimicrobial agent to treat foodborne bacterial infections and inflammation. Supplementary Information The online version contains supplementary material available at 10.1007/s10068-022-01087-y.
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Wu R, Patocka J, Nepovimova E, Oleksak P, Valis M, Wu W, Kuca K. Marine Invertebrate Peptides: Antimicrobial Peptides. Front Microbiol 2022; 12:785085. [PMID: 34975806 PMCID: PMC8719109 DOI: 10.3389/fmicb.2021.785085] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 11/15/2021] [Indexed: 12/11/2022] Open
Abstract
Antimicrobial peptides are an important component of many organisms’ innate immune system, with a good inhibitory or killing effect against the invading pathogens. As a type of biological polypeptide with natural immune activities, antimicrobial peptides have a broad spectrum of antibacterial, antiviral, and antitumor activities. Nevertheless, these peptides cause no harm to the organisms themselves. Compared with traditional antibiotics, antimicrobial peptides have the advantage of not producing drug resistance and have a unique antibacterial mechanism, which has attracted widespread attention. In this study, marine invertebrates were classified into arthropods, annelids, mollusks, cnidarians, and tunicata. We then analyzed the types, sources and antimicrobial activities of the antimicrobial peptides in each group. We also reviewed the immune mechanism from three aspects: membrane-targeted direct killing effects, non-membrane targeting effects and immunomodulatory effects. Finally, we discussed their applications and the existing problems facing antimicrobial peptides in actual production. The results are expected to provide theoretical support for future research and applications of antimicrobial peptides in marine invertebrates.
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Affiliation(s)
- Ran Wu
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Jiri Patocka
- Department of Radiology and Toxicology, Faculty of Health and Social Studies, University of South Bohemia in České Budějovice, České Budějovice, Czechia.,Biomedical Research Centre, University Hospital Hradec Králové, Hradec Králové, Czechia
| | - Eugenie Nepovimova
- Department of Chemistry, Faculty of Science, University of Hradec Králové, Hradec Králové, Czechia
| | - Patrik Oleksak
- Department of Chemistry, Faculty of Science, University of Hradec Králové, Hradec Králové, Czechia
| | - Martin Valis
- Department of Neurology, Faculty of Medicine, University Hospital Hradec Králové, Charles University, Hradec Králové, Czechia
| | - Wenda Wu
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China.,Department of Chemistry, Faculty of Science, University of Hradec Králové, Hradec Králové, Czechia
| | - Kamil Kuca
- Biomedical Research Centre, University Hospital Hradec Králové, Hradec Králové, Czechia.,Department of Chemistry, Faculty of Science, University of Hradec Králové, Hradec Králové, Czechia
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Design of RGDS Peptide-Immobilized Self-Assembling β-Strand Peptide from Barnacle Protein. Int J Mol Sci 2021; 22:ijms22031240. [PMID: 33513895 PMCID: PMC7866236 DOI: 10.3390/ijms22031240] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 01/22/2021] [Accepted: 01/25/2021] [Indexed: 11/17/2022] Open
Abstract
We designed three types of RGD-containing barnacle adhesive proteins using self-assembling peptides. In the present study, three types of RGD-containing peptides were synthesized by solid-phase peptide synthesis, and the secondary structures of these peptides were analyzed by CD and FT-IR spectroscopy. The mechanical properties of peptide hydrogels were characterized by a rheometer. We discuss the correlation between the peptide conformation, and cell attachment and cell spreading activity from the viewpoint of developing effective tissue engineering scaffolds. We created a peptide-coated cell culture substrate by coating peptides on a polystyrene plate. They significantly facilitated cell adhesion and spreading compared to a non-coated substrate. When the RGDS sequence was modified at N- or C-terminal of R-Y, it was found that the self-assembling ability was dependent on the strongly affects hydrogel formation and cell adhesion caused by its secondary structure.
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8
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Chitosan-Based Thermo-Sensitive Hydrogel Loading Oyster Peptides for Hemostasis Application. MATERIALS 2020; 13:ma13215038. [PMID: 33182319 PMCID: PMC7664874 DOI: 10.3390/ma13215038] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Revised: 11/02/2020] [Accepted: 11/04/2020] [Indexed: 02/01/2023]
Abstract
Uncontrolled massive hemorrhage is one of the principal causes of death in trauma emergencies. By using catechol-modified chitosan (CS-C) as the matrix material and β glycerol phosphate (β-GP) as a thermo-sensitive agent, chitosan-based thermo-sensitive hydrogel loading oyster peptides (CS-C/OP/β-GP) were prepared at physiological temperature. The hemostatic performance of CS-C/OP/β-GP hydrogel was tested in vivo and in vitro, and its biological safety was evaluated. The results showed that the in vitro coagulation time and blood coagulation index of CS-C/OP/β-GP hydrogel were better than those of a commercial gelatin sponge. Notably, compared with the gelatin sponge, CS-C/OP/β-GP hydrogel showed that the platelet adhesion and erythrocyte adsorption rates were 38.98% and 95.87% higher, respectively. Additionally, the hemostasis time in mouse liver injury was shortened by 19.5%, and the mass of blood loss in the mouse tail amputation model was reduced by 18.9%. The safety evaluation results demonstrated that CS-C/OP/β-GP had no cytotoxicity to L929 cells, and the hemolysis rates were less than 5% within 1 mg/mL, suggesting good biocompatibility. In conclusion, our results indicate that CS-C/OP/β-GP is expected to be a promising dressing in the field of medical hemostasis.
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Lv C, Han Y, Yang D, Zhao J, Wang C, Mu C. Antibacterial activities and mechanisms of action of a defensin from manila clam Ruditapes philippinarum. FISH & SHELLFISH IMMUNOLOGY 2020; 103:266-276. [PMID: 32439511 DOI: 10.1016/j.fsi.2020.05.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 04/28/2020] [Accepted: 05/09/2020] [Indexed: 06/11/2023]
Abstract
Defensins represent an evolutionary ancient family of antimicrobial peptides, which played an undeniably important role in host defense. In the present study, a defensin isoform was identified and characterized from manila clam Ruditapes philippinarum (designed as Rpdef1α). Multiple alignments and phylogenetic analysis suggested that Rpdef1α belonged to the defensin family. Quantitative RT-PCR and immunohistochemical analysis revealed that Rpdef1α transcripts and the encoding peptide were dominantly expressed in the tissues of gills and mantle. After Vibrio anguillarum challenge, the Rpdef1α transcripts were significantly up-regulated in gills of clams. In addition, rRpdef1α not only showed broad-spectrum antimicrobial activities towards Vibrio species, but also inhibited the formation of bacterial biofilms. Knockdown of Rpdef1α transcripts caused significant increase in the cumulative mortality of manila clams post V. anguillarum challenge. Membrane integrity, scanning electron microscopy analysis and electrochemical assay indicated that rRpdef1α was capable of causing bacterial membrane permeabilization and then resulted in cell death. Moreover, phagocytosis and chemotactic ability of hemocytes could be significantly enhanced after incubation with rRpdef1α. Overall, these results suggested that Rpdef1α could act as both antibacterial agent and opsonin to defend against the invading microorganisms in manila clam R. philippinarum.
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Affiliation(s)
- Chengjie Lv
- Key Laboratory of Applied Marine Biotechnology, Ministry of Education, School of Marine Sciences, Ningbo University, Ningbo, 315832, PR China; Collaborative Innovation Center for Zhejiang Marine High-efficiency and Healthy Aquaculture, Ningbo, 315832, PR China
| | - Yijing Han
- Research and Development Center for Efficient Utilization of Coastal Bioresources, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Dinglong Yang
- Research and Development Center for Efficient Utilization of Coastal Bioresources, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, PR China; Center for Ocean Mega-science, Chinese Academy of Sciences, Qingdao, Shandong, 266071, PR China.
| | - Jianmin Zhao
- Research and Development Center for Efficient Utilization of Coastal Bioresources, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, PR China; Center for Ocean Mega-science, Chinese Academy of Sciences, Qingdao, Shandong, 266071, PR China
| | - Chunlin Wang
- Key Laboratory of Applied Marine Biotechnology, Ministry of Education, School of Marine Sciences, Ningbo University, Ningbo, 315832, PR China; Collaborative Innovation Center for Zhejiang Marine High-efficiency and Healthy Aquaculture, Ningbo, 315832, PR China
| | - Changkao Mu
- Key Laboratory of Applied Marine Biotechnology, Ministry of Education, School of Marine Sciences, Ningbo University, Ningbo, 315832, PR China; Collaborative Innovation Center for Zhejiang Marine High-efficiency and Healthy Aquaculture, Ningbo, 315832, PR China.
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10
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Zhou Y, Zhou QJ, Qiao Y, Chen J, Li MY. The host defense peptide β-defensin confers protection against Vibrio anguillarum in ayu, Plecoglossus altivelis. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2020; 103:103511. [PMID: 31580833 DOI: 10.1016/j.dci.2019.103511] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 09/27/2019] [Accepted: 09/27/2019] [Indexed: 06/10/2023]
Abstract
β-defensin is a cationic host defense peptide actively participating in host innate immune response against pathogens. In teleost fish, β-defensin exhibits a diversity in genotypes and functions. Herein, a β-defensin homolog (PaBD) was identified from ayu, Plecoglossus altivelis, showing multiple tissues' upregulation against Vibrio anguillarum challenge. In vivo experiments revealed that intraperitoneal injection of chemically synthesized mature PaBD (mPaBD) increased the survival rate of V. anguillarum-infected ayu, accompanied by reduced bacterial load and decreased tissue mRNA levels of tumor necrosis factor α (PaTNF-α) and interleukin 1β (PaIL-1β). However, in vitro, mPaBD showed weak bactericidal activity against V. anguillarum. Interestingly, mPaBD enhanced phagocytosis, intracellular bacterial killing, and respiratory burst of ayu monocytes/macrophages (MO/MΦ). Moreover, it inhibited mRNA levels of PaIL-1β and PaTNF-α in MO/MФ upon V. anguillarum infection. In conclusion, PaBD protects ayu against V. anguillarum challenge not only through its direct antibacterial ability, but also through its immunomodulation in MO/MΦ.
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Affiliation(s)
- Yan Zhou
- State Key Laboratory for Quality and Safety of Agro-products, Ningbo University, Ningbo, 315211, China; Laboratory of Biochemistry and Molecular Biology, School of Marine Sciences, Ningbo University, Ningbo, 315832, China
| | - Qian-Jin Zhou
- State Key Laboratory for Quality and Safety of Agro-products, Ningbo University, Ningbo, 315211, China; Laboratory of Biochemistry and Molecular Biology, School of Marine Sciences, Ningbo University, Ningbo, 315832, China
| | - Yan Qiao
- Laboratory of Biochemistry and Molecular Biology, School of Marine Sciences, Ningbo University, Ningbo, 315832, China
| | - Jiong Chen
- State Key Laboratory for Quality and Safety of Agro-products, Ningbo University, Ningbo, 315211, China; Laboratory of Biochemistry and Molecular Biology, School of Marine Sciences, Ningbo University, Ningbo, 315832, China; Key Laboratory of Applied Marine Biotechnology of Ministry of Education, Ningbo University, Ningbo, 315832, China.
| | - Ming-Yun Li
- Laboratory of Biochemistry and Molecular Biology, School of Marine Sciences, Ningbo University, Ningbo, 315832, China
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Yao T, Lu J, Ye L, Wang J. Molecular characterization and immune analysis of a defensin from small abalone, Haliotis diversicolor. Comp Biochem Physiol B Biochem Mol Biol 2019; 235:1-7. [PMID: 31078702 DOI: 10.1016/j.cbpb.2019.05.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 04/18/2019] [Accepted: 05/06/2019] [Indexed: 01/09/2023]
Abstract
As one of antimicrobial peptides (AMPs), defensins are involved in invertebrate innate immunity against invading pathogens. In this study, a member of the invertebrate defensins was cloned and characterized from the small abalone Haliotis diversicolor, designated HdDef-2. The HdDef-2 cDNA contained a 201 bp open reading frame encoding 66 amino acids including a signal peptide of 18 amino acids and a mature peptide of 48 amino acids. The mature peptide of HdDef-2 possessed similar features to other AMPs, such as lower molecular mass, net positive charge (+1), and a high hydrophobic residue ratio (45%). In addition, six cysteines in the mature peptide were arranged in the pattern C-X16-C-X3-C-X9-C-X4-C-X1-C and stabilized the α-helix/β-sheet motif (CSαβ) with three disulfide bonds (C1-C4, C2-C5 and C3-C6) in the predicted tertiary structure. Moreover, the similar three-dimensional structure to Anopheles gambiae defensin and a phylogenetic analysis suggest that HdDef-2 may be a new member of the arthropod defensin family. Quantitative real-time PCR analysis revealed that HdDef-2 transcripts were constitutively expressed in the mantle, gill, hepatopancreas, and foot, with the highest level in the hepatopancreas. It was observed that HdDef-2 transcripts were significantly induced in the hepatopancreas after infection by Vibrio harveyi. These results indicate that HdDef-2 may be involved in the immune response against invading pathogenic bacteria, but future work is needed to verify its antimicrobial activity in protein level and elucidate the underlying mechanisms.
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Affiliation(s)
- Tuo Yao
- Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou Guangdong 510300, PR China
| | - Jie Lu
- Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou Guangdong 510300, PR China
| | - Lingtong Ye
- Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou Guangdong 510300, PR China
| | - Jiangyong Wang
- Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou Guangdong 510300, PR China.
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