1
|
Ortega L, Carrera C, Muñoz-Flores C, Salazar S, Villegas MF, Starck MF, Valenzuela A, Agurto N, Montesino R, Astuya A, Parra N, Pérez ET, Santibáñez N, Romero A, Ruíz P, Lamazares E, Reyes F, Sánchez O, Toledo JR, Acosta J. New insight into the biological activity of Salmo salar NK-lysin antimicrobial peptides. Front Immunol 2024; 15:1191966. [PMID: 38655253 PMCID: PMC11035819 DOI: 10.3389/fimmu.2024.1191966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Accepted: 02/23/2024] [Indexed: 04/26/2024] Open
Abstract
NK-lysin is a potent antimicrobial peptide (AMP) with antimicrobial activity against bacteria, fungi, viruses, and parasites. NK-lysin is a type of granulysin, a member of the saposin-like proteins family first isolated from a pig's small intestine. In previous work, for the first time, we identified four variants of nk-lysin from Atlantic salmon (Salmo salar) using EST sequences. In the present study, we reported and characterized two additional transcripts of NK-lysin from S. salar. Besides, we evaluated the tissue distribution of three NK-lysins from S. salar and assessed the antimicrobial, hemolytic, and immunomodulatory activities and signaling pathways of three NK-lysin-derived peptides. The synthetic peptides displayed antimicrobial activity against Piscirickettsia salmonis (LF-89) and Flavobacterium psychrophilum. These peptides induced the expression of immune genes related to innate and adaptive immune responses in vitro and in vivo. The immunomodulatory activity of the peptides involves the mitogen-activated protein kinases-mediated signaling pathway, including p38, extracellular signal-regulated kinase 1/2, and/or c-Jun N-terminal kinases. Besides, the peptides modulated the immune response induced by pathogen-associated molecular patterns (PAMPs). Our findings show that NK-lysin could be a highly effective immunostimulant or vaccine adjuvant for use in fish aquaculture.
Collapse
Affiliation(s)
- Leonardo Ortega
- Laboratorio de Biotecnología y Biofármacos, Departamento de Fisiopatología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Crisleri Carrera
- Laboratorio de Biotecnología y Biofármacos, Departamento de Fisiopatología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Carolina Muñoz-Flores
- Laboratorio de Biotecnología y Biofármacos, Departamento de Fisiopatología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Santiago Salazar
- Laboratorio de Biotecnología y Biofármacos, Departamento de Fisiopatología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Milton F. Villegas
- Laboratorio de Biotecnología y Biofármacos, Departamento de Fisiopatología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - María F. Starck
- Laboratorio de Biotecnología y Biofármacos, Departamento de Fisiopatología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Ariel Valenzuela
- Laboratorio de Piscicultura y Patología Acuática, Departamento de Oceanografía, Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Concepción, Chile
| | - Niza Agurto
- Laboratorio de Piscicultura y Patología Acuática, Departamento de Oceanografía, Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Concepción, Chile
| | - Raquel Montesino
- Laboratorio de Biotecnología y Biofármacos, Departamento de Fisiopatología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Allisson Astuya
- Laboratorio de Genómica Marina y Cultivo Celular, Departamento de Oceanografía y Centro de Investigación Oceanográfica en el Pacífico Sur Oriental (COPAS) Sur-Austral, Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Concepción, Chile
| | - Natalie Parra
- Laboratorio de Biotecnología y Biofármacos, Departamento de Fisiopatología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Ercilia T. Pérez
- Laboratorio de Inmunología y Estrés de Organismos Acuáticos, Instituto de Patología Animal, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
- Centro Fondo de Financiamiento de Centros de Investigación en Áreas Prioritarias (FONDAP), Interdisciplinary Center for Aquaculture Research (INCAR), Universidad de Concepción, Concepción, Chile
| | - Natacha Santibáñez
- Laboratorio de Inmunología y Estrés de Organismos Acuáticos, Instituto de Patología Animal, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
- Centro Fondo de Financiamiento de Centros de Investigación en Áreas Prioritarias (FONDAP), Interdisciplinary Center for Aquaculture Research (INCAR), Universidad de Concepción, Concepción, Chile
| | - Alex Romero
- Laboratorio de Inmunología y Estrés de Organismos Acuáticos, Instituto de Patología Animal, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
- Centro Fondo de Financiamiento de Centros de Investigación en Áreas Prioritarias (FONDAP), Interdisciplinary Center for Aquaculture Research (INCAR), Universidad de Concepción, Concepción, Chile
| | - Pamela Ruíz
- Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Talcahuano, Chile
| | - Emilio Lamazares
- Laboratorio de Biotecnología y Biofármacos, Departamento de Fisiopatología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Fátima Reyes
- Laboratorio de Biofármacos Recombinantes, Departamento de Farmacología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Oliberto Sánchez
- Laboratorio de Biofármacos Recombinantes, Departamento de Farmacología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Jorge R. Toledo
- Laboratorio de Biotecnología y Biofármacos, Departamento de Fisiopatología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Jannel Acosta
- Laboratorio de Biotecnología y Biofármacos, Departamento de Fisiopatología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| |
Collapse
|
2
|
Yang Y, Song X, Cui N, Lei T, Huang Y, Shi Y, Hu Y, Zhou X, Zhao Z. Functional characterization of obscure puffer ToNK-lysin: A novel immunomodulator possessing anti-bacterial and anti-inflammatory properties. FISH & SHELLFISH IMMUNOLOGY 2023; 142:109080. [PMID: 37748586 DOI: 10.1016/j.fsi.2023.109080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 09/10/2023] [Accepted: 09/14/2023] [Indexed: 09/27/2023]
Abstract
NK-lysins are one of the most abundant antimicrobial peptides produced by cytotoxic T lymphocytes (CTLs) and natural killer cells (NKs), and identified as a new class of intrinsically disordered proteins, playing critical roles in the cell-mediated cytotoxicity response, as well as immunomodulatory and antimicrobial activities upon a significant range of pathogens. In the present study, an NK-lysin was identified from Obscure puffer Takifugu obscurus (ToNK-lysin). The open reading frame of ToNK-lysin sequence spans 423 bp, encoding a peptide with 140 amino acids which shares a moderate residue identity (18%-60%) with NK-lysin of mammals and other teleost species. Phylogenetic analysis revealed that ToNK-lysin was most closely related to NK-lysins from the Pleuronectiformes (Bastard halibut Paralichthys olivaceus and Pacific halibut Hippoglossus stenolepis). Comprehensive computational analysis revealed that ToNK-lysin have substantial level of intrinsic disorder, which might be contribute to its multifunction. The transcripts of the ToNK-lysin were detected in multiple examined tissues and most abundant in gills. After bacterial and Poly I:C challenge, the transcriptional levels of ToNK-lysin were significantly up-regulated in the head kidney, liver and spleen at different time points. The recombinant ToNK-lysin showed significant antibacterial activity against Vibrio harveyi and Escherichia coli, and the ToNK-lysin treatment not only reduced the bacterial loads in liver and head kidney, but also alleviated the pathogen-mediated upregulation of immune-related genes. In addition, the co-incubation with rToNK-lysin protein remarkably degraded bacterial genomic DNA, suggesting the potential mechanism of ToNK-lysin against microbes. These results suggest that ToNK-lysin possess antibacterial and immunoregulatory function both in vivo and in vitro, which may allow it a potential applicability to the aquaculture industry.
Collapse
Affiliation(s)
- Yaxing Yang
- Jiangsu Province Engineering Research Center for Marine Bio-resources Sustainable Utilization, Hohai University, Nanjing 210024, China; Department of Marine Biology, College of Oceanography, Hohai University, Nanjing 210024, China
| | - Xiaorui Song
- Jiangsu Province Engineering Research Center for Marine Bio-resources Sustainable Utilization, Hohai University, Nanjing 210024, China; Department of Marine Biology, College of Oceanography, Hohai University, Nanjing 210024, China
| | - Nan Cui
- Jiangsu Province Engineering Research Center for Marine Bio-resources Sustainable Utilization, Hohai University, Nanjing 210024, China; Department of Marine Biology, College of Oceanography, Hohai University, Nanjing 210024, China
| | - Tianying Lei
- Jiangsu Province Engineering Research Center for Marine Bio-resources Sustainable Utilization, Hohai University, Nanjing 210024, China; Department of Marine Biology, College of Oceanography, Hohai University, Nanjing 210024, China
| | - Ying Huang
- Jiangsu Province Engineering Research Center for Marine Bio-resources Sustainable Utilization, Hohai University, Nanjing 210024, China; Department of Marine Biology, College of Oceanography, Hohai University, Nanjing 210024, China
| | - Yan Shi
- Jiangsu Province Engineering Research Center for Marine Bio-resources Sustainable Utilization, Hohai University, Nanjing 210024, China; Department of Marine Biology, College of Oceanography, Hohai University, Nanjing 210024, China
| | - Yadong Hu
- Jiangsu Innovation Center of Marine Bioresource, Jiangsu Coast Development Group Co., Ltd, Nanjing, 210019, China
| | - Xinghu Zhou
- Jiangsu Innovation Center of Marine Bioresource, Jiangsu Coast Development Group Co., Ltd, Nanjing, 210019, China
| | - Zhe Zhao
- Jiangsu Province Engineering Research Center for Marine Bio-resources Sustainable Utilization, Hohai University, Nanjing 210024, China; Department of Marine Biology, College of Oceanography, Hohai University, Nanjing 210024, China.
| |
Collapse
|
3
|
Huang Y, Wu B, Yang Y, Li W, Han F. Cloning, subcellular localization and antibacterial functional analysis of NK-lysin in yellow drum (Nibea albiflora). FISH & SHELLFISH IMMUNOLOGY 2023; 141:109061. [PMID: 37683807 DOI: 10.1016/j.fsi.2023.109061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 08/22/2023] [Accepted: 09/04/2023] [Indexed: 09/10/2023]
Abstract
Vibrio harveyi is the primary pathogenic bacteria affecting Nibea albiflora aquaculture. In a previous phase, our laboratory intentionally exposed N. albiflora to V. harveyi and analyzed the outcomes using a combination of genome-wide association study (GWAS) and RNA-seq. The results revealed that the antimicrobial peptide NK-lysin (YdNkl-1) was a candidate gene for resistance to V. harveyi disease in N. albiflora. To investigate the role of the antimicrobial peptide NK-lysin in N. albiflora's antimicrobial immunity, we screened the YdNkl-1 gene from the transcriptome database. The full-length cDNA of YdNkl-1 gene is 508 bp, with an open reading frame (ORF) of 477 bp, encoding 158 amino acids. The deduced amino acid sequence of YdNkl-1 contains a signal peptide (1st-22nd amino acids) and a Saposin B domain (50th-124th amino acids), akin to mammalian NK-lysin. Phylogenetic tree analysis confirmed that the NK-lysin of teleost fish clustered into a single species, and YdNkl-1 was most closely related to Larimichthys crocea. Subcellular localization showed that YdNkl-1 was distributed in cytoplasm and nucleus of yellow drum kidney cells. Furthermore, YdNkl-1 mRNA transcripts were significantly up-regulated in the skin, gill, intestine, head-kidney, liver, and spleen after V. harveyi infection, suggesting a critical role in N. albiflora's defense against V. harveyi infection. Additionally, we purified and observed the YdNkl-1 protein, which exhibited a potent membrane-disrupting effect on V. harveyi, Pseudomonas plecoglossicida, Vibrio parahaemolyticus, Escherichia coli and Bacillus subtilis. These findings underscore the significance of NK-lysin in N. albiflora's resistance to V. harveyi infection and provide new insights into the crucial role of NK-lysin in the innate immunity of teleost fishes.
Collapse
Affiliation(s)
- Ying Huang
- Key Laboratory of Healthy Mariculture for the East China Sea, Fujian Provincial Key Laboratory of Marine Fishery Resources and Eco-environment, Fisheries College, Jimei University, Xiamen, 361000, PR China
| | - Baolan Wu
- Key Laboratory of Healthy Mariculture for the East China Sea, Fujian Provincial Key Laboratory of Marine Fishery Resources and Eco-environment, Fisheries College, Jimei University, Xiamen, 361000, PR China
| | - Yao Yang
- Key Laboratory of Healthy Mariculture for the East China Sea, Fujian Provincial Key Laboratory of Marine Fishery Resources and Eco-environment, Fisheries College, Jimei University, Xiamen, 361000, PR China
| | - Wanbo Li
- Key Laboratory of Healthy Mariculture for the East China Sea, Fujian Provincial Key Laboratory of Marine Fishery Resources and Eco-environment, Fisheries College, Jimei University, Xiamen, 361000, PR China
| | - Fang Han
- Key Laboratory of Healthy Mariculture for the East China Sea, Fujian Provincial Key Laboratory of Marine Fishery Resources and Eco-environment, Fisheries College, Jimei University, Xiamen, 361000, PR China.
| |
Collapse
|
4
|
Sánchez F, Lozano-Muñoz I, Muñoz S, Diaz N, Neira R, Wacyk J. Effect of dietary inclusion of microalgae (Nannochloropsis gaditana and Schizochytrium spp) on non-specific immunity and erythrocyte maturity in Atlantic salmon fingerlings. FISH & SHELLFISH IMMUNOLOGY 2023; 140:108975. [PMID: 37488040 DOI: 10.1016/j.fsi.2023.108975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 07/07/2023] [Accepted: 07/21/2023] [Indexed: 07/26/2023]
Abstract
The parr-smolt transformation in salmonids involves a critical period characterized by systemic changes associated with the fish's immune response. In this context, as a dietary ingredient in functional diets, microalgae offer an alternative due to their nutritional and bioactive compounds that could strengthen the immune status. This study evaluated the effect of a diet supplemented with Schizochytrium spp and Nannochloropsis gaditana on the expression of genes associated with the antibacterial response. Additionally, the study assessed the effect on the leukocyte population and erythrocyte maturity in Salmo salar blood. Fish were fed for 30 days with a microalgal mixture (1:1) at a 10% inclusion. Each diet was randomly assigned to a tank using a completely randomized design (CRD) with four replications. Each tank was stocked with 70 Atlantic salmon fingerlings with an initial mean weight of 78.87 ± 0.84. Transcription levels were quantified and analyzed by qRT-PCR from cell isolates and mucus tissue. Furthermore, cell count and identification of leukocytes and classification of cellular maturity of erythrocytes using a neural network with a multilayer perceptron (MLP) were performed. Our results showed a significant (p < 0.05) increase in fold change expression of C3 (2.54 ± 0.65) and NK-Lysine (6.84 ± 0.94) in erythrocytes of microalgae-supplemented fish. Moreover, a significant increase of 1.59 and 2.35 times in monocytes and immature erythrocytes, respectively, was observed in the same group of fish (p < 0.05). This study's results indicate that dual microalgae (Schizochytrium spp and N. gaditana) supplementation can increase innate humoral antibacterial components, particularly in erythrocyte tissue, and increase phagocytic cells and immature erythrocytes in S. salar blood.
Collapse
Affiliation(s)
- Felipe Sánchez
- Facultad de Ciencias Agronómicas, Departamento de Producción Animal, Laboratorio de Nutrición Animal, Universidad de Chile, Santa Rosa, 11315, La Pintana, CP, 8820808, Santiago, Región Metropolitana, Chile
| | - Ivonne Lozano-Muñoz
- Facultad de Ciencias Agronómicas, Departamento de Producción Animal, Laboratorio de Nutrición Animal, Universidad de Chile, Santa Rosa, 11315, La Pintana, CP, 8820808, Santiago, Región Metropolitana, Chile
| | - Susana Muñoz
- Facultad de Ciencias Agronómicas, Departamento de Producción Animal, Laboratorio de Nutrición Animal, Universidad de Chile, Santa Rosa, 11315, La Pintana, CP, 8820808, Santiago, Región Metropolitana, Chile
| | - Nelson Diaz
- Facultad de Ciencias Agronómicas, Departamento de Producción Animal, Laboratorio de Nutrición Animal, Universidad de Chile, Santa Rosa, 11315, La Pintana, CP, 8820808, Santiago, Región Metropolitana, Chile
| | - Roberto Neira
- Facultad de Ciencias Agronómicas, Departamento de Producción Animal, Laboratorio de Nutrición Animal, Universidad de Chile, Santa Rosa, 11315, La Pintana, CP, 8820808, Santiago, Región Metropolitana, Chile
| | - Jurij Wacyk
- Facultad de Ciencias Agronómicas, Departamento de Producción Animal, Laboratorio de Nutrición Animal, Universidad de Chile, Santa Rosa, 11315, La Pintana, CP, 8820808, Santiago, Región Metropolitana, Chile.
| |
Collapse
|
5
|
Wang CB, Yan X, Wang GH, Liu WQ, Wang Y, Hao DF, Liu HM, Zhang M. NKHs27, a sevenband grouper NK-Lysin peptide that possesses immunoregulatory and antimicrobial activity. FISH & SHELLFISH IMMUNOLOGY 2023; 136:108715. [PMID: 37001746 DOI: 10.1016/j.fsi.2023.108715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Revised: 03/22/2023] [Accepted: 03/26/2023] [Indexed: 06/19/2023]
Abstract
As an effective and broad-spectrum antimicrobial peptide, NK-Lysin is attracted more and more attention at present. However, the functions and action mechanism of NK-Lysin peptides are still not comprehensive enough at present. In this study, a sevenband grouper (Hyporthodus septemfasciatus) NK-Lysin peptide, NKHs27, was identified and synthesized, and its biological functions were studied. The results indicated that NKHs27 shares 44.44%∼88.89% overall sequence identities with other teleost NK-Lysin peptides. The following antibacterial activity assay exhibited that NKHs27 was active against both Gram-negative and Gram-positive bacteria, including Staphylococcus aureus, Listonella anguillarum, Vibrio parahaemolyticus and Vibrio vulnificus. Additionally, NKHs27 showed a synergistic effect when it was combined with rifampicin or erythromycin. In the process of interaction with the L. anguillarum cells, NKHs27 changed the cell membrane permeability and retained its morphological integrity, then penetrated into the cytoplasm to act on genomic DNA or total RNA. Then, in vitro studies showed that NKHs27 could enhance the respiratory burst ability of macrophages and upregulate immune-related genes expression in it. Moreover, NKHs27 incubation improved the proliferation of peripheral blood leukocytes significantly. Finally, in vivo studies showed that administration of NKHs27 prior to bacterial infection significantly reduced pathogen dissemination and replication in tissues. In summary, these results provide new insights into the function of NK-Lysin peptides in teleost and support that NKHs27, as a novel broad-spectrum antibacterial peptide, has potential applications in aquaculture against pathogenic infections.
Collapse
Affiliation(s)
- Chang-Biao Wang
- School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, Shandong Province, 266109, China
| | - Xue Yan
- School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, Shandong Province, 266109, China
| | - Guang-Hua Wang
- School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, Shandong Province, 266109, China
| | - Wen-Qing Liu
- School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, Shandong Province, 266109, China
| | - Yue Wang
- School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, Shandong Province, 266109, China
| | - Dong-Fang Hao
- School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, Shandong Province, 266109, China
| | - Hong-Mei Liu
- School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, Shandong Province, 266109, China
| | - Min Zhang
- School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, Shandong Province, 266109, China; Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao, Shandong Province, 266109, China.
| |
Collapse
|
6
|
Tong J, Guan X, Jiang S, Sun L. A saposin domain-containing protein of tongue sole Cynoglossus semilaevis: Antimicrobial activity and mechanism. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2023; 141:104633. [PMID: 36610645 DOI: 10.1016/j.dci.2023.104633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2022] [Revised: 01/03/2023] [Accepted: 01/03/2023] [Indexed: 06/17/2023]
Abstract
Prosaposin is a precursor that can be processed into four different saposins, designated as A, B, C, and D, which have multiple functions in mammals, including neuroprotection and immune modulation. The immune function of saposin in teleost remains largely unknown. In the present study, a saposin (SAP) domain-containing protein was identified in half-smooth tongue sole Cynoglossus semilaevis and named CsSDP. CsSDP harbors one SAP A domain and two SAP B domains. When expressed in HEK293T cells, CsSDP was specifically localized in the lysosome. When overexpressed in Escherichia coli, CsSDP markedly inhibited bacterial growth, and the inhibitory effect depended on two specific regions in the SAP A and SAP B domains. Two polypeptides (P32 and P30) derived from the above SAP A and B domains could bind to and inhibit the growth of both Gram-negative and Gram-positive bacteria. The ultrastructural analysis revealed that P32 and P30 killed target bacteria by disrupting the bacterial cell wall and inducing substantial release of cytoplasmic contents. These results shed new lights on the immune function of saposin domain-containing protein in teleost.
Collapse
Affiliation(s)
- Jiazhou Tong
- College of Life Sciences, Qingdao Agricultural University, Qingdao, China; CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, China
| | - Xiaolu Guan
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, China; Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, China
| | - Shuai Jiang
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, China; Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, China.
| | - Li Sun
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, China; Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, China.
| |
Collapse
|
7
|
A Non-Canonical Teleost NK-Lysin: Antimicrobial Activity via Multiple Mechanisms. Int J Mol Sci 2022; 23:ijms232112722. [PMID: 36361512 PMCID: PMC9654944 DOI: 10.3390/ijms232112722] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 10/19/2022] [Accepted: 10/20/2022] [Indexed: 01/25/2023] Open
Abstract
NK-lysin (NKL) is a family of antimicrobial proteins with an important role in innate and adaptive immunity. In this study, a non-canonical NK-lysin (NKLnc) was identified in the Japanese flounder (Paralichthys olivaceus), which shares low sequence identities (15.8-20.6%) with previously reported fish NKLs and was phylogenetically separated from the canonical NKLs in teleost. NKLnc expression was upregulated in flounder tissues during bacterial infection, and interference with NKLnc expression impaired the ability of flounder cells to eliminate invading bacteria. When expressed in Escherichia coli, NKLnc was detrimental to the host cells. P35, a peptide derived from the saposin B domain (SapB) of NKLnc, bound major bacterial surface molecules and killed both Gram-negative and Gram-positive bacteria by inflicting damage to bacterial cell structure and genomic DNA. The bactericidal activity, but not the bacteria-binding capacity, of P35 required the structural integrity of the alpha 2/3 helices in SapB. Furthermore, P35 induced the migration of flounder peripheral blood leukocytes, inhibited bacterial dissemination in fish tissues, and facilitated fish survival after bacterial challenge. Together our study reveals that NKLnc plays an important part in flounder immune defense, and that NKLnc peptide exerts an antimicrobial effect via multiple mechanisms by targeting both bacteria and fish cells.
Collapse
|
8
|
Chen RY, Chen J, Liu ZM, Lin ZH, Guo ZP. Barbel steed (Hemibarbus labeo) NK-lysin protects against Aeromonas hydrophila infection via immunomodulatory activity. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2021; 122:104114. [PMID: 33945835 DOI: 10.1016/j.dci.2021.104114] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 04/27/2021] [Accepted: 04/27/2021] [Indexed: 06/12/2023]
Abstract
NK-lysins (NKLs) are a family of multifunctional antimicrobial peptides that have activity against various microorganisms. However, the immunomodulatory activity of NKL in fish remains unclear. In this study, the cDNA sequence of barbel steed (Hemibarbus labeo) NKL gene was cloned. Barbel steed NKL amino acid sequence comprised a signal peptide and a mature peptide. The saposin B domain in the mature peptide has six conserved cysteines that form three disulfide bonds. Phylogenetic analysis showed that the barbel steed NKL was most closely related to that of the common carp (Cyprinus carpio) NKL. Differential expression analysis showed that the barbel steed NKL gene was expressed in all tested tissues, with the highest expression in the spleen. In response to Aeromonas hydrophila infection, NKL was significantly upregulated in the liver, spleen, head kidney, and gill. The barbel steed NKL showed strong antibacterial activity against Vibrio parahaemolyticus, V. alginolyticus, V. vulnificus, and Listeria monocytogenes. However, NKL had no antibacterial activity against the pathogenic bacteria A. hydrophila. Lactate dehydrogenase release assays showed that NKL damaged the V. parahaemolyticus cell membrane. NKL significantly increased barbel steed survival rate after A. hydrophila infection and upregulated IL-1β and TNF-α expression in the spleen and head kidney. NKL induced monocyte/macrophage chemotaxis and enhanced the respiratory burst and proinflammatory cytokine expression. Our study shows that fish NKL exhibits immunomodulatory effects and protects the host from pathogenic infections independent of direct bacterial clearance.
Collapse
Affiliation(s)
- Ru-Yi Chen
- College of Ecology, Lishui University, Lishui, 323000, China
| | - Jie Chen
- College of Ecology, Lishui University, Lishui, 323000, China.
| | - Zi-Ming Liu
- College of Ecology, Lishui University, Lishui, 323000, China
| | - Zhi-Hua Lin
- College of Ecology, Lishui University, Lishui, 323000, China.
| | - Zhi-Ping Guo
- College of Ecology, Lishui University, Lishui, 323000, China
| |
Collapse
|