1
|
Jensen KT, Nielsen NS, Viana Almeida A, Thøgersen IB, Enghild JJ, Harwood SL. Proteolytic cleavage of the TGFβ co-receptor CD109 changes its conformation, resulting in protease inhibition via activation of its thiol ester, and dissociation from the cell membrane. FEBS J 2024; 291:3169-3190. [PMID: 38587194 DOI: 10.1111/febs.17128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 02/14/2024] [Accepted: 03/18/2024] [Indexed: 04/09/2024]
Abstract
The glycosylphosphatidylinositol (GPI)-anchored protein cluster of differentiation 109 (CD109) is expressed on many human cell types and modulates the transforming growth factor β (TGF-β) signaling network. CD109 belongs to the alpha-macroglobulin family of proteins, known for their protease-triggered conformational changes. However, the effect of proteolysis on CD109 and its conformation are unknown. Here, we investigated the interactions of CD109 with proteases. We found that a diverse selection of proteases cleaved peptide bonds within the predicted bait region of CD109, inducing a conformational change that activated the thiol ester of CD109. We show CD109 was able to conjugate proteases with this thiol ester and decrease their activity toward protein substrates, demonstrating that CD109 is a protease inhibitor. We additionally found that CD109 has a unique mechanism whereby its GPI-anchored macroglobulin 8 (MG8) domain dissociates during its conformational change, allowing proteases to release CD109 from the cell surface by a precise mechanism and not unspecific shedding. We conclude that proteolysis of the CD109 bait region affects both its structure and location, and that interactions between CD109 and proteases may be important to understanding its functions, for example, as a TGF-β co-receptor.
Collapse
Affiliation(s)
| | | | - Ana Viana Almeida
- Department of Molecular Biology and Genetics, Aarhus University, Denmark
| | - Ida B Thøgersen
- Department of Molecular Biology and Genetics, Aarhus University, Denmark
| | - Jan J Enghild
- Department of Molecular Biology and Genetics, Aarhus University, Denmark
| | | |
Collapse
|
2
|
Wang B, Zhong X, Fields L, Lu H, Zhu Z, Li L. Structural Proteomic Profiling of Cerebrospinal Fluids to Reveal Novel Conformational Biomarkers for Alzheimer's Disease. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2023; 34:459-471. [PMID: 36745855 PMCID: PMC10276618 DOI: 10.1021/jasms.2c00332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Alzheimer's disease (AD) is the most common representation of dementia, with brain pathological hallmarks of protein abnormal aggregation, such as with amyloid beta and tau protein. It is well established that posttranslational modifications on tau protein, particularly phosphorylation, increase the likelihood of its aggregation and subsequent formation of neurofibrillary tangles, another hallmark of AD. As additional misfolded proteins presumably exist distinctly in AD disease states, which would serve as potential source of AD biomarkers, we used limited proteolysis-coupled with mass spectrometry (LiP-MS) to probe protein structural changes. After optimizing the LiP-MS conditions, we further applied this method to human cerebrospinal fluid specimens collected from healthy control, mild cognitive impairment (MCI), and AD subject groups to characterize proteome-wide misfolding tendencies as a result of disease progression. The fully tryptic peptides embedding LiP sites were compared with the half-tryptic peptides generated from internal cleavage of the same region to determine any structural unfolding or misfolding. We discovered hundreds of significantly up- and down-regulated peptides associated with MCI and AD indicating their potential structural changes in AD progression. Moreover, we detected 53 structurally changed regions in 12 proteins with high confidence between the healthy control and disease groups, illustrating the functional relevance of these proteins with AD progression. These newly discovered conformational biomarker candidates establish valuable future directions for exploring the molecular mechanism of designing therapeutic targets for AD.
Collapse
Affiliation(s)
- Bin Wang
- School of Pharmacy, University of Wisconsin-Madison, Madison, WI, 53705, United States
| | - Xiaofang Zhong
- School of Pharmacy, University of Wisconsin-Madison, Madison, WI, 53705, United States
| | - Lauren Fields
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, United States
| | - Haiyan Lu
- School of Pharmacy, University of Wisconsin-Madison, Madison, WI, 53705, United States
| | - Zexin Zhu
- School of Pharmacy, University of Wisconsin-Madison, Madison, WI, 53705, United States
| | - Lingjun Li
- School of Pharmacy, University of Wisconsin-Madison, Madison, WI, 53705, United States
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, United States
- Lachman Institute for Pharmaceutical Development, School of Pharmacy, University of Wisconsin-Madison, Madison, WI 53705, United States
- Wisconsin Center for NanoBioSystems, School of Pharmacy, University of Wisconsin-Madison, Madison, WI 53705, United States
| |
Collapse
|
3
|
Harwood SL, Diep K, Nielsen NS, Jensen KT, Enghild JJ. The conformational change of the protease inhibitor α 2-macroglobulin is triggered by the retraction of the cleaved bait region from a central channel. J Biol Chem 2022; 298:102230. [PMID: 35787371 PMCID: PMC9352918 DOI: 10.1016/j.jbc.2022.102230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 06/24/2022] [Accepted: 06/26/2022] [Indexed: 11/04/2022] Open
Abstract
The protease inhibitor α2-macroglobulin (A2M) is a member of the ancient α2-macroglobulin superfamily (A2MF), which also includes structurally related proteins, such as complement factor C3. A2M and other A2MF proteins undergo an extensive conformational change upon cleavage of their bait region by proteases. However, the mechanism whereby cleavage triggers the change has not yet been determined. We have previously shown that A2M remains functional after completely replacing its bait region with glycine and serine residues. Here, we use this tabula rasa bait region to investigate several hypotheses for the triggering mechanism. When tabula rasa bait regions containing disulfide loops were elongated by reducing the disulfides, we found that A2M remained in its native conformation. In addition, cleavage within a disulfide loop did not trigger the conformational change until after the disulfide was reduced, indicating that the introduction of discontinuity into the bait region is essential to the trigger. Previously, A2MF structures have shown that the C-terminal end of the bait region (a.k.a. the N-terminal region of the truncated α chain) threads through a central channel in native A2MF proteins. Bait region cleavage abolishes this plug-in-channel arrangement, as the bait region retracts from the channel and the channel itself collapses. We found that mutagenesis of conserved plug-in-channel residues disrupted the formation of native A2M. These results provide experimental evidence for a structural hypothesis in which retraction of the bait region from this channel following cleavage and the channel’s subsequent collapse triggers the conformational change of A2M and other A2MF proteins.
Collapse
Affiliation(s)
| | - Khang Diep
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus 8000, Denmark
| | - Nadia Sukusu Nielsen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus 8000, Denmark
| | | | - Jan J Enghild
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus 8000, Denmark.
| |
Collapse
|
4
|
Wang Y, Zhai J, Yang C, Wang J, Sun Y, Li Y, Ju Z, Huang J, Wang C. Complement component 3 haplotypes influence serum complement activity and milk production traits in Chinese Holstein cattle. PLoS One 2022; 17:e0268959. [PMID: 35771868 PMCID: PMC9246146 DOI: 10.1371/journal.pone.0268959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 05/12/2022] [Indexed: 12/03/2022] Open
Abstract
Complement component 3 (C3) is the key molecule of the three pathways of complement activation (alternative, classical, and lectin pathways), which are involved in phagocytosis, inflammation, and immunoregulation processes to destroy infectious microorganisms. In this study, three novel single-nucleotide polymorphisms (SNPs) (g.-1293C>G located in the 5′-flanking region, g.56T>C in exon I, and g.7017C>T in exon XII) of the C3 gene were detected using created restriction site polymerase chain reaction, restriction fragment length polymorphism, and DNA sequencing in 952 cattle from three Chinese breeds. The genotypes and haplotypes were analyzed to investigate the polymorphisms and their possible implications, with particular investigative focus on their associations with serum C3 level, complement hemolytic activity (CH50 and ACH50), and milk production traits. The g.56T>C SNP in exon I affected the serum ACH50 (P<0.01) and the milk somatic cell score (SCS) (P<0.05), and the g.7017C>T SNP in exon XII significantly affected the serum ACH50 values (P<0.01). Moreover, statistical analyses revealed that individuals with genotypic combination CCC/GCC showed significantly lower SCS and the lowest C3 concentration in serum compared with cows with CCC/GTT (P = 0.0007) and CTT/CTT (P = 0.0021); the individuals with CCC/CCT had significantly higher ACH50 values than those with CCC/CTC (P = 0.0008) and CTC/GTC (P = 0.001); cows with CCT/CTT had higher values of CH50 and 305-day milk yield (P>0.05). The C3 expression levels were significantly increased in lung and mammary tissues (P<0.05), while significantly decreased in heart, spleen, liver, and kidney tissues in mastitis cows compared with those in healthy animals (P<0.01), respectively. Bacterial counts of serum antibacterial activities were also completed to verify the effect of SNPs on resistance to mastitis pathogens. Genetically resistant cows (CCC/GCC) had serum with noticeably higher antibacterial activity against S. aureus and E. coli in vitro than the genetically susceptible CCC/GTT cows (P<0.05). Results from this study imply that the C3 gene plays a role in resistance to bacterial infection and that it can be used as a molecular marker for complement activity and traits related to milk production.
Collapse
Affiliation(s)
- Yonghui Wang
- College of Agronomy, Liaocheng University, Liaocheng City, Shandong Province, P. R. China
| | - Junyu Zhai
- College of Agronomy, Liaocheng University, Liaocheng City, Shandong Province, P. R. China
| | - Chunhong Yang
- Dairy Cattle Research Center, Shandong Academy of Agricultural Science, Jinan City, Shandong Province, P. R. China
| | - Jingpeng Wang
- Dairy Cattle Research Center, Shandong Academy of Agricultural Science, Jinan City, Shandong Province, P. R. China
| | - Yan Sun
- College of Agronomy, Liaocheng University, Liaocheng City, Shandong Province, P. R. China
| | - Yuhua Li
- College of Agronomy, Liaocheng University, Liaocheng City, Shandong Province, P. R. China
| | - Zhihua Ju
- Dairy Cattle Research Center, Shandong Academy of Agricultural Science, Jinan City, Shandong Province, P. R. China
| | - Jingming Huang
- Dairy Cattle Research Center, Shandong Academy of Agricultural Science, Jinan City, Shandong Province, P. R. China
| | - Changfa Wang
- College of Agronomy, Liaocheng University, Liaocheng City, Shandong Province, P. R. China
- * E-mail:
| |
Collapse
|
5
|
Huang X, Wang Y, Yu C, Zhang H, Ru Q, Li X, Song K, Zhou M, Zhu P. Cryo-EM structures reveal the dynamic transformation of human alpha-2-macroglobulin working as a protease inhibitor. SCIENCE CHINA. LIFE SCIENCES 2022; 65:2491-2504. [PMID: 35781771 DOI: 10.1007/s11427-022-2139-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2022] [Accepted: 06/06/2022] [Indexed: 10/17/2022]
Abstract
Human alpha-2-macroglobulin is a well-known inhibitor of a broad spectrum of proteases and plays important roles in immunity, inflammation, and infections. Here, we report the cryo-EM structures of human alpha-2-macroglobulin in its native state, induced state transformed by its authentic substrate, human trypsin, and serial intermediate states between the native and fully induced states. These structures exhibit distinct conformations, which reveal the dynamic transformation of alpha-2-macro-globulin that acts as a protease inhibitor. The results shed light on the molecular mechanism of alpha-2-macroglobulin in entrapping substrates.
Collapse
Affiliation(s)
- Xiaoxing Huang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
| | - Youwang Wang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Cong Yu
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Hui Zhang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Qiang Ru
- The Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences (CAMS) and Peking Union Medical College (PUMC), Beijing, 100193, China
| | - Xinxin Li
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Kai Song
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
| | - Min Zhou
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
| | - Ping Zhu
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China. .,University of Chinese Academy of Sciences, Beijing, 100049, China.
| |
Collapse
|
6
|
Nielsen NS, Zarantonello A, Harwood SL, Jensen KT, Kjøge K, Thøgersen IB, Schauser L, Karlsen JL, Andersen GR, Enghild JJ. Cryo-EM structures of human A2ML1 elucidate the protease-inhibitory mechanism of the A2M family. Nat Commun 2022; 13:3033. [PMID: 35641520 PMCID: PMC9156758 DOI: 10.1038/s41467-022-30758-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 05/12/2022] [Indexed: 12/26/2022] Open
Abstract
A2ML1 is a monomeric protease inhibitor belonging to the A2M superfamily of protease inhibitors and complement factors. Here, we investigate the protease-inhibitory mechanism of human A2ML1 and determine the structures of its native and protease-cleaved conformations. The functional inhibitory unit of A2ML1 is a monomer that depends on covalent binding of the protease (mediated by A2ML1’s thioester) to achieve inhibition. In contrast to the A2M tetramer which traps proteases in two internal chambers formed by four subunits, in protease-cleaved monomeric A2ML1 disordered regions surround the trapped protease and may prevent substrate access. In native A2ML1, the bait region is threaded through a hydrophobic channel, suggesting that disruption of this arrangement by bait region cleavage triggers the extensive conformational changes that result in protease inhibition. Structural comparisons with complement C3/C4 suggest that the A2M superfamily of proteins share this mechanism for the triggering of conformational change occurring upon proteolytic activation. A2ML1 is a human protease inhibitor belonging to the A2M protein family. In this study, the authors determine structures of A2ML1 before and after protease inhibition and investigate its mechanism of action.
Collapse
Affiliation(s)
- Nadia Sukusu Nielsen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Alessandra Zarantonello
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark.,Cordeliers Research Center, Sorbonne University, Paris, France
| | | | | | - Katarzyna Kjøge
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Ida B Thøgersen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | | | | | - Gregers R Andersen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark.
| | - Jan J Enghild
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark.
| |
Collapse
|
7
|
Harwood SL, Nielsen NS, Diep K, Jensen KT, Nielsen PK, Yamamoto K, Enghild JJ. Development of selective protease inhibitors via engineering of the bait region of human α 2-macroglobulin. J Biol Chem 2021; 297:100879. [PMID: 34139236 PMCID: PMC8267569 DOI: 10.1016/j.jbc.2021.100879] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 06/02/2021] [Accepted: 06/13/2021] [Indexed: 01/15/2023] Open
Abstract
Human α2-macroglobulin (A2M) is an abundant protease inhibitor in plasma, which regulates many proteolytic processes and is involved in innate immunity. A2M’s unique protease-trapping mechanism of inhibition is initiated when a protease cleaves within the exposed and highly susceptible “bait region.” As the wild-type bait region is permissive to cleavage by most human proteases, A2M is accordingly a broad-spectrum protease inhibitor. In this study, we extensively modified the bait region in order to identify any potential functionally important elements in the bait region sequence and to engineer A2M proteins with restrictive bait regions, which more selectively inhibit a target protease. A2M in which the bait region was entirely replaced by glycine-serine repeats remained fully functional and was not cleaved by any tested protease. Therefore, this bait region was designated as the “tabula rasa” bait region and used as the starting point for further bait region engineering. Cleavage of the tabula rasa bait region by specific proteases was conveyed by the insertion of appropriate substrate sequences, e.g., basic residues for trypsin. Screening and optimization of tabula rasa bait regions incorporating matrix metalloprotease 2 (MMP2) substrate sequences produced an A2M that was specifically cleaved by MMPs and inhibited MMP2 cleavage activity as efficiently as wild-type A2M. We propose that this approach can be used to develop A2M-based protease inhibitors, which selectively inhibit target proteases, which might be applied toward the clinical inhibition of dysregulated proteolysis as occurs in arthritis and many types of cancer.
Collapse
Affiliation(s)
- Seandean Lykke Harwood
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark; Global Research Technologies, Novo Nordisk A/S, Måløv, Denmark
| | - Nadia Sukusu Nielsen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Khang Diep
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | | | | | - Kazuhiro Yamamoto
- Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Jan J Enghild
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark.
| |
Collapse
|
8
|
Harwood SL, Lyngsø J, Zarantonello A, Kjøge K, Nielsen PK, Andersen GR, Pedersen JS, Enghild JJ. Structural Investigations of Human A2M Identify a Hollow Native Conformation That Underlies Its Distinctive Protease-Trapping Mechanism. Mol Cell Proteomics 2021; 20:100090. [PMID: 33964423 PMCID: PMC8167298 DOI: 10.1016/j.mcpro.2021.100090] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 04/07/2021] [Accepted: 05/02/2021] [Indexed: 12/21/2022] Open
Abstract
Human α2-macroglobulin (A2M) is the most characterized protease inhibitor in the alpha-macroglobulin (αM) superfamily, but the structure of its native conformation has not been determined. Here, we combined negative stain electron microscopy (EM), small-angle X-ray scattering (SAXS), and cross-linking-mass spectrometry (XL-MS) to investigate native A2M and its collapsed conformations that are obtained through aminolysis of its thiol ester by methylamine or cleavage of its bait region by trypsin. The combined interpretation of these data resulted in a model of the native A2M tetramer and its conformational changes. Native A2M consists of two crescent-shaped disulfide-bridged subunit dimers, which face toward each other and surround a central hollow space. In native A2M, interactions across the disulfide-bridged dimers are minimal, with a single major interface between the linker (LNK) regions of oppositely positioned subunits. Bait region cleavage induces both intrasubunit domain repositioning and an altered configuration of the disulfide-bridged dimer. These changes collapse the tetramer into a more compact conformation, which encloses an interior protease-trapping cavity. A recombinant A2M with a modified bait region was used to map the bait region's position in native A2M by XL-MS. A second recombinant A2M introduced an intersubunit disulfide into the LNK region, demonstrating the predicted interactions between these regions in native A2M. Altogether, our native A2M model provides a structural foundation for understanding A2M's protease-trapping mechanism, its conformation-dependent receptor interactions, and the dissociation of native A2M into dimers due to inflammatory oxidative stress.
Collapse
Affiliation(s)
- Seandean Lykke Harwood
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark; Global Research Technologies, Novo Nordisk A/S, Måløv, Denmark
| | - Jeppe Lyngsø
- Interdisciplinary Nanoscience Center, Aarhus University, Aarhus, Denmark; Department of Chemistry, Aarhus University, Aarhus, Denmark
| | | | - Katarzyna Kjøge
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | | | - Gregers Rom Andersen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Jan Skov Pedersen
- Interdisciplinary Nanoscience Center, Aarhus University, Aarhus, Denmark; Department of Chemistry, Aarhus University, Aarhus, Denmark.
| | - Jan J Enghild
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark; Interdisciplinary Nanoscience Center, Aarhus University, Aarhus, Denmark.
| |
Collapse
|
9
|
Hou ZS, Xin YR, Yang XD, Zeng C, Zhao HK, Liu MQ, Zhang MZ, Daniel JG, Li JF, Wen HS. Transcriptional Profiles of Genes Related to Stress and Immune Response in Rainbow Trout ( Oncorhynchus mykiss) Symptomatically or Asymptomatically Infected With Vibrio anguillarum. Front Immunol 2021; 12:639489. [PMID: 33968031 PMCID: PMC8097155 DOI: 10.3389/fimmu.2021.639489] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 03/11/2021] [Indexed: 12/29/2022] Open
Abstract
Rainbow trout (Oncorhynchus mykiss) is one of the most common aquaculture fish species worldwide. Vibriosis disease outbreaks cause significant setbacks to aquaculture. The stress and immune responses are bidirectionally modulated in response to the health challenges. Therefore, an investigation into the regulatory mechanisms of the stress and immune responses in trout is invaluable for identifying potential vibriosis treatments. We investigated the transcriptional profiles of genes associated with stress and trout immune functions after Vibrio anguillarum infection. We compared the control trout (CT, 0.9% saline injection), asymptomatic trout (AT, surviving trout with minor or no symptoms after bacteria injection), and symptomatic trout (ST, moribund trout with severe symptoms after bacteria injection). Our results showed activated immunomodulatory genes in the cytokine network and downregulated glucocorticoid and mineralocorticoid receptors in both AT and ST, indicating activation of the proinflammatory cytokine cascade as a common response in AT and ST. Moreover, the AT specifically activated the complement- and TNF-associated immune defenses in response to V. anguillarum infection. However, the complement and coagulation cascades, as well as steroid hormone homeostasis in ST, were disturbed by V. anguillarum. Our studies provide new insights toward understanding regulatory mechanisms in stress and immune functions in response to diseases.
Collapse
Affiliation(s)
- Zhi-Shuai Hou
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education (KLMME), Ocean University of China, Qingdao, China
| | - Yuan-Ru Xin
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education (KLMME), Ocean University of China, Qingdao, China
| | - Xiao-Dong Yang
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education (KLMME), Ocean University of China, Qingdao, China
| | - Chu Zeng
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education (KLMME), Ocean University of China, Qingdao, China
| | - Hong-Kui Zhao
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education (KLMME), Ocean University of China, Qingdao, China
| | - Meng-Qun Liu
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education (KLMME), Ocean University of China, Qingdao, China
| | - Mei-Zhao Zhang
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education (KLMME), Ocean University of China, Qingdao, China
| | - Jeffrey G Daniel
- Department of Anatomy, Physiology, and Pharmacology, Auburn University College of Veterinary Medicine, Auburn, AL, United States
| | - Ji-Fang Li
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education (KLMME), Ocean University of China, Qingdao, China
| | - Hai-Shen Wen
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education (KLMME), Ocean University of China, Qingdao, China
| |
Collapse
|
10
|
Jiang B, Zhang Z, Xu J, Jin H, Li Y. Cloning and structural analysis of complement component 3d in wild birds provides insight into its functional evolution. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2021; 117:103979. [PMID: 33338517 DOI: 10.1016/j.dci.2020.103979] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 10/08/2020] [Accepted: 12/13/2020] [Indexed: 06/12/2023]
Abstract
Complement component 3 d (C3d) is the final cleavage product of the complement component C3 and serves as a crucial role in link innate and adaptive immunity, and increase B-cell sensitivity to an antigen by 1000-10000 fold. The crystal structure of human C3d revealed there are two distinct surfaces, a convex surface containing the thioester-constituting residues that mediate covalent binding to the target antigen, and a concave surface with an acidic pocket responsible for interaction with CR2. In this study, we cloned and sequenced cDNA fragment encoding C3d region from 15 wild bird species. Then, the C3d sequences from wild birds, chicken and mammals were aligned to construct phylogenetic trees. Phylogenetic tree displayed two main branches, indicating mammals and birds, but the bird C3d branch was divided into two main parts, with five wild birds (Ardeola bacchus, Zoothera, Bubo, Crossoptilon mantchuricum and Caprimulgus europaeus) clustering much closer to mammals. In addition, the C3d proteins of Ardeola bacchus, Bubo, Crossoptilon mantchuricum and Caprimulgus europaeus contained a Glu163 residue at the position at which Lys163 was found in other birds. However, Glu163 have the same charge polarity as Asp163, which is the key amino acid residue comprising the acidic pocket combined with CR2 found at this position in mammals, and Zoothera also possessed Asp163 at this position. Structure modeling analyses also verified that the C3ds of these five wild bird species exhibited the amino acid sequence and structure comprising the typical acidic pocket found in mammals that is required for combination with B cell surface receptors, which contribute electrostatic forces to interact with CR2. Our investigations indicate that some bird C3ds may already have the ability to bind with CR2 by electrostatic force, like mammals. As Ardeola bacchus, Zoothera, Bubo, Crossoptilon mantchuricum and Caprimulgus europaeus have more typical C3d concave acid pockets and thus a stronger ability to bind CR2, we speculate that these five wild birds may have a solider immunity against pathogens. Our phylogenetic and structural analyses of bird C3ds provide insights on the evolutionary divergence in the function of immune factors of avian and mammalian.
Collapse
Affiliation(s)
- Bo Jiang
- Institute of Animal Husbandry and Veterinary Medicine, Beijing Academy of Agricultural and Forestry Sciences, Beijing, 100097, PR China
| | - Zhenhua Zhang
- Institute of Animal Husbandry and Veterinary Medicine, Beijing Academy of Agricultural and Forestry Sciences, Beijing, 100097, PR China
| | - Jian Xu
- Institute of Animal Husbandry and Veterinary Medicine, Beijing Academy of Agricultural and Forestry Sciences, Beijing, 100097, PR China
| | - Huan Jin
- Institute of Animal Husbandry and Veterinary Medicine, Beijing Academy of Agricultural and Forestry Sciences, Beijing, 100097, PR China
| | - Yongqing Li
- Institute of Animal Husbandry and Veterinary Medicine, Beijing Academy of Agricultural and Forestry Sciences, Beijing, 100097, PR China.
| |
Collapse
|
11
|
Wang Y, Zhou S, Wang D, Wei T, Zhu J, Li Z. Complement C4-A and Plasminogen as Potential Biomarkers for Prediction of Papillary Thyroid Carcinoma. Front Endocrinol (Lausanne) 2021; 12:737638. [PMID: 34803909 PMCID: PMC8603925 DOI: 10.3389/fendo.2021.737638] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 09/17/2021] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Early diagnosis and therapy of papillary thyroid carcinoma (PTC) is essential for reducing recurrence and improving the long-term survival. In this study, we aimed to investigate the proteome profile of plasma and screen unique proteins which could be used as a biomarker for predicting PTC. METHODS Serum samples were collected from 29 PTC patients and 29 nodular goiter (NG) patients. Five PTC serum samples and five NG serum samples were selected for proteome profiles by proteomics. Eight proteins in PTC and NG serum samples were selected for confirmation by enzyme-linked immunosorbent assay analysis. Receiver operating characteristic curves was used to evaluate the diagnostic value of potential biomarkers. RESULTS Complement C4-A (C4A) and plasminogen (PLG) were significantly lower in serum samples of PTC patients compared with NG patients. C4A was observed to have excellent diagnostic accuracy for PTC, with a sensitivity of 91.67% and specificity of 83.33%. The diagnostic value of PLG for PTC was demonstrated by a sensitivity at 87.50% and specificity at 75.00%. The AUC for C4A and PLG was 0.97 ± 0.02 and 0.89 ± 0.05. CONCLUSION C4A and PLG appeared to be excellent potential biomarkers for the prediction of PTC.
Collapse
Affiliation(s)
- Yichao Wang
- Department of Thyroid & Parathyroid Surgery Center, West China Hospital, Sichuan University, Chengdu, China
- Laboratory of Thyroid and Parathyroid Disease, Frontiers Science Center for Disease-related Molecular Network, West China Hospital, Sichuan University, Chengdu, China
| | - Shengliang Zhou
- Department of Thyroid & Parathyroid Surgery Center, West China Hospital, Sichuan University, Chengdu, China
- Laboratory of Thyroid and Parathyroid Disease, Frontiers Science Center for Disease-related Molecular Network, West China Hospital, Sichuan University, Chengdu, China
- West China School of Medicine, West China Hospital, Sichuan University, Chengdu, China
| | - Dun Wang
- Department of Thyroid & Parathyroid Surgery Center, West China Hospital, Sichuan University, Chengdu, China
- Laboratory of Thyroid and Parathyroid Disease, Frontiers Science Center for Disease-related Molecular Network, West China Hospital, Sichuan University, Chengdu, China
- West China School of Medicine, West China Hospital, Sichuan University, Chengdu, China
| | - Tao Wei
- Department of Thyroid & Parathyroid Surgery Center, West China Hospital, Sichuan University, Chengdu, China
- Laboratory of Thyroid and Parathyroid Disease, Frontiers Science Center for Disease-related Molecular Network, West China Hospital, Sichuan University, Chengdu, China
| | - Jingqiang Zhu
- Department of Thyroid & Parathyroid Surgery Center, West China Hospital, Sichuan University, Chengdu, China
- Laboratory of Thyroid and Parathyroid Disease, Frontiers Science Center for Disease-related Molecular Network, West China Hospital, Sichuan University, Chengdu, China
| | - Zhihui Li
- Department of Thyroid & Parathyroid Surgery Center, West China Hospital, Sichuan University, Chengdu, China
- *Correspondence: Zhihui Li,
| |
Collapse
|
12
|
Harwood SL, Nielsen NS, Pedersen H, Kjøge K, Nielsen PK, Andersen GR, Enghild JJ. Substituting the Thiol Ester of Human A2M or C3 with a Disulfide Produces Native Proteins with Altered Proteolysis-Induced Conformational Changes. Biochemistry 2020; 59:4799-4809. [DOI: 10.1021/acs.biochem.0c00803] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Seandean Lykke Harwood
- Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus, Denmark
- Global Research Technologies, Novo Nordisk A/S, Novo Nordisk Park, 2760 Måløv, Denmark
| | - Nadia Sukusu Nielsen
- Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus, Denmark
| | - Henrik Pedersen
- Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus, Denmark
| | - Katarzyna Kjøge
- Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus, Denmark
| | - Peter Kresten Nielsen
- Global Research Technologies, Novo Nordisk A/S, Novo Nordisk Park, 2760 Måløv, Denmark
| | - Gregers Rom Andersen
- Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus, Denmark
| | - Jan J. Enghild
- Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus, Denmark
| |
Collapse
|
13
|
Harwood SL, Nielsen NS, Jensen KT, Nielsen PK, Thøgersen IB, Enghild JJ. α 2-Macroglobulin-like protein 1 can conjugate and inhibit proteases through their hydroxyl groups, because of an enhanced reactivity of its thiol ester. J Biol Chem 2020; 295:16732-16742. [PMID: 32978260 PMCID: PMC7864068 DOI: 10.1074/jbc.ra120.015694] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 09/18/2020] [Indexed: 11/08/2022] Open
Abstract
Proteins in the α-macroglobulin (αM) superfamily use thiol esters to form covalent conjugation products upon their proteolytic activation. αM protease inhibitors use theirs to conjugate proteases and preferentially react with primary amines (e.g. on lysine side chains), whereas those of αM complement components C3 and C4B have an increased hydroxyl reactivity that is conveyed by a conserved histidine residue and allows conjugation to cell surface glycans. Human α2-macroglobulin-like protein 1 (A2ML1) is a monomeric protease inhibitor but has the hydroxyl reactivity-conveying histidine residue. Here, we have investigated the role of hydroxyl reactivity in a protease inhibitor by comparing recombinant WT A2ML1 and the A2ML1 H1084N mutant in which this histidine is removed. Both of A2ML1s' thiol esters were reactive toward the amine substrate glycine, but only WT A2ML1 reacted with the hydroxyl substrate glycerol, demonstrating that His-1084 increases the hydroxyl reactivity of A2ML1's thiol ester. Although both A2ML1s conjugated and inhibited thermolysin, His-1084 was required for the conjugation and inhibition of acetylated thermolysin, which lacks primary amines. Using MS, we identified an ester bond formed between a thermolysin serine residue and the A2ML1 thiol ester. These results demonstrate that a histidine-enhanced hydroxyl reactivity can contribute to protease inhibition by an αM protein. His-1084 did not improve A2ML1's protease inhibition at pH 5, indicating that A2ML1's hydroxyl reactivity is not an adaption to its acidic epidermal environment.
Collapse
Affiliation(s)
- Seandean Lykke Harwood
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark; General Research Technologies, Novo Nordisk A/S, Måløv, Denmark
| | - Nadia Sukusu Nielsen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | | | | | - Ida B Thøgersen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Jan J Enghild
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark.
| |
Collapse
|
14
|
Pedersen H, Jensen RK, Hansen AG, Gadeberg TAF, Thiel S, Laursen NS, Andersen GR. A C3-specific nanobody that blocks all three activation pathways in the human and murine complement system. J Biol Chem 2020; 295:8746-8758. [PMID: 32376685 DOI: 10.1074/jbc.ra119.012339] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 04/28/2020] [Indexed: 12/18/2022] Open
Abstract
The complement system is a tightly controlled proteolytic cascade in the innate immune system, which tags intruding pathogens and dying host cells for clearance. An essential protein in this process is complement component C3. Uncontrolled complement activation has been implicated in several human diseases and disorders and has spurred the development of therapeutic approaches that modulate the complement system. Here, using purified proteins and several biochemical assays and surface plasmon resonance, we report that our nanobody, hC3Nb2, inhibits C3 deposition by all complement pathways. We observe that the hC3Nb2 nanobody binds human native C3 and its degradation products with low nanomolar affinity and does not interfere with the endogenous regulation of C3b deposition mediated by Factors H and I. Using negative stain EM analysis and functional assays, we demonstrate that hC3Nb2 inhibits the substrate-convertase interaction by binding to the MG3 and MG4 domains of C3 and C3b. Furthermore, we notice that hC3Nb2 is cross-reactive and inhibits the lectin and alternative pathway in murine serum. We conclude that hC3Nb2 is a potent, general, and versatile inhibitor of the human and murine complement cascades. Its cross-reactivity suggests that this nanobody may be valuable for analysis of complement activation within animal models of both acute and chronic diseases.
Collapse
Affiliation(s)
- Henrik Pedersen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Rasmus K Jensen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | | | - Trine A F Gadeberg
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Steffen Thiel
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Nick S Laursen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Gregers R Andersen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark.
| |
Collapse
|
15
|
Jia BB, Jin CD, Li MF. The trypsin-like serine protease domain of Paralichthys olivaceus complement factor I regulates complement activation and inhibits bacterial growth. FISH & SHELLFISH IMMUNOLOGY 2020; 97:18-26. [PMID: 31830570 DOI: 10.1016/j.fsi.2019.12.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 12/07/2019] [Accepted: 12/09/2019] [Indexed: 06/10/2023]
Abstract
In mammals, complement factor I (CFI) is a serine protease in serum and plays a pivotal role in the regulation of complement activation. In the presence of cofactor, CFI cleaves C3b to iC3b, and further degrades iC3b to C3c and C3d. In teleost, the function of CFI is poorly understood. In this study, we examined the immunological property of CFI from Japanese flounder (Paralichthys olivaceus) (PoCFI), a teleost species with important economic value. PoCFI is composed of 597 amino acid residues and possesses a trypsin-like serine protease (Tryp) domain. We found that PoCFI expressions occurred in nine different tissues and were upregulated by bacterial challenge. Recombinant PoCFI-Tryp (rPoCFI-Tryp) inhibited complement activation and degraded C3b in serum. rPoCFI-Tryp exhibited apparent binding capacities to a board-spectrum of bacteria and inhibited bacterial growth. These results provide the first evidence to indicate that CFI in teleost negatively regulates complement activation via degradation C3b, and probably plays a role in host immune defense against bacterial infection.
Collapse
Affiliation(s)
- Bei-Bei Jia
- CAS Key Laboratory of Experimental Marine Biology, CAS Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China; Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology Qingdao, China; University of Chinese Academy of Sciences, Beijing, China
| | - Cheng-Dong Jin
- CAS Key Laboratory of Experimental Marine Biology, CAS Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China; Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology Qingdao, China; University of Chinese Academy of Sciences, Beijing, China
| | - Mo-Fei Li
- CAS Key Laboratory of Experimental Marine Biology, CAS Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China; Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology Qingdao, China.
| |
Collapse
|
16
|
Williams M, Contet A, Hou CFD, Levashina EA, Baxter RHG. Anopheles gambiae TEP1 forms a complex with the coiled-coil domain of LRIM1/APL1C following a conformational change in the thioester domain. PLoS One 2019; 14:e0218203. [PMID: 31237887 PMCID: PMC6592522 DOI: 10.1371/journal.pone.0218203] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Accepted: 05/28/2019] [Indexed: 12/23/2022] Open
Abstract
The complement-like protein thioester-containing protein 1 (TEP1) is a key factor in the immune response of the malaria vector Anopheles gambiae to pathogens. Multiple allelic variants of TEP1 have been identified in laboratory strains and in the field, and are correlated with distinct immunophenotypes. TEP1 is tightly regulated by conformational changes induced by cleavage in a protease-sensitive region. Cleaved TEP1 forms exhibit significant variation in stability from hours to days at room temperature. In particular, the refractory allele TEP1*R1 is significantly more stable than the susceptible allele TEP1*S1. This raises the question of whether the stability of cleaved TEP1 is linked to allelic variation and varying immunophenotypes. We have analyzed the stability of the cleaved form of additional TEP1 alleles and constructs. We show that stability is correlated with allelic variation within two specific loops in direct proximity to the thioester bond. The variable loops are part of an interface between the TED and MG8 domains of TEP1 that protect the thioester from hydrolysis. Engineering specific disulfide bonds to prevent separation of the TED-MG8 interface stabilizes the cleaved form of TEP1 for months at room temperature. Cleaved TEP1 forms a soluble complex with a heterodimer of two leucine-rich repeat proteins, LRIM1 and APL1C, and precipitates in the absence of this complex. The molecular structure and oligomeric state of the TEP1/LRIM1/APL1C complex is unclear. The C-terminal coiled-coil domain of the LRIM1/APL1C complex is sufficient to stabilize the cleaved form of TEP1 in solution but cleaved forms of disulfide-stabilized TEP1 do not interact with LRIM1/APL1C. This implies that formation of the TEP1cut/LRIM1/APL1C complex is related to the conformational change that induces the precipitation of cleaved TEP1.
Collapse
Affiliation(s)
- Marni Williams
- Dept. of Chemistry, Yale University, New Haven, Connecticut, United States of America
- Dept. of Molecular Biophysics & Biochemistry, Yale University, New Haven, Connecticut, United States of America
| | - Alicia Contet
- Dept. of Chemistry, Yale University, New Haven, Connecticut, United States of America
- Dept. of Molecular Biophysics & Biochemistry, Yale University, New Haven, Connecticut, United States of America
| | - Chun-Feng David Hou
- Dept. of Medical Genetics & Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania, United States of America
| | - Elena A. Levashina
- Vector Biology Unit, Max Planck Institute for Infection Biology, Berlin, Germany
| | - Richard H. G. Baxter
- Dept. of Chemistry, Yale University, New Haven, Connecticut, United States of America
- Dept. of Molecular Biophysics & Biochemistry, Yale University, New Haven, Connecticut, United States of America
- Dept. of Medical Genetics & Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania, United States of America
- * E-mail:
| |
Collapse
|
17
|
Jensen RK, Pihl R, Gadeberg TAF, Jensen JK, Andersen KR, Thiel S, Laursen NS, Andersen GR. A potent complement factor C3-specific nanobody inhibiting multiple functions in the alternative pathway of human and murine complement. J Biol Chem 2018; 293:6269-6281. [PMID: 29497000 PMCID: PMC5925797 DOI: 10.1074/jbc.ra117.001179] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 02/07/2018] [Indexed: 12/30/2022] Open
Abstract
The complement system is a complex, carefully regulated proteolytic cascade for which suppression of aberrant activation is of increasing clinical relevance, and inhibition of the complement alternative pathway is a subject of intense research. Here, we describe the nanobody hC3Nb1 that binds to multiple functional states of C3 with subnanomolar affinity. The nanobody causes a complete shutdown of alternative pathway activity in human and murine serum when present in concentrations comparable with that of C3, and hC3Nb1 is shown to prevent proconvertase assembly, as well as binding of the C3 substrate to C3 convertases. Our crystal structure of the C3b-hC3Nb1 complex and functional experiments demonstrate that proconvertase formation is blocked by steric hindrance between the nanobody and an Asn-linked glycan on complement factor B. In addition, hC3Nb1 is shown to prevent factor H binding to C3b, rationalizing its inhibition of factor I activity. Our results identify hC3Nb1 as a versatile, inexpensive, and powerful inhibitor of the alternative pathway in both human and murine in vitro model systems of complement activation.
Collapse
Affiliation(s)
| | - Rasmus Pihl
- Biomedicine, Aarhus University, DK-8000 Aarhus, Denmark
| | | | - Jan K. Jensen
- From the Departments of Molecular Biology and Genetics and
| | | | - Steffen Thiel
- Biomedicine, Aarhus University, DK-8000 Aarhus, Denmark
| | | | - Gregers R. Andersen
- From the Departments of Molecular Biology and Genetics and , To whom correspondence should be addressed:
Dept. of Molecular Biology and Genetics, Aarhus University, Gustav Wieds Vej 10C, DK-8000 Aarhus, Denmark. Tel.:
45-5144-6530; Fax:
45-8619-6500; E-mail:
| |
Collapse
|
18
|
Iyer A, Xu W, Reid RC, Fairlie DP. Chemical Approaches to Modulating Complement-Mediated Diseases. J Med Chem 2017; 61:3253-3276. [DOI: 10.1021/acs.jmedchem.7b00882] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Abishek Iyer
- Centre for Inflammation and Disease Research, Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia
- ARC Centre of Excellence in Advanced Molecular Imaging, Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Weijun Xu
- ARC Centre of Excellence in Advanced Molecular Imaging, Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Robert C. Reid
- ARC Centre of Excellence in Advanced Molecular Imaging, Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia
| | - David P. Fairlie
- Centre for Inflammation and Disease Research, Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia
- ARC Centre of Excellence in Advanced Molecular Imaging, Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia
| |
Collapse
|
19
|
Bayly-Jones C, Bubeck D, Dunstone MA. The mystery behind membrane insertion: a review of the complement membrane attack complex. Philos Trans R Soc Lond B Biol Sci 2017; 372:20160221. [PMID: 28630159 PMCID: PMC5483522 DOI: 10.1098/rstb.2016.0221] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/08/2016] [Indexed: 12/14/2022] Open
Abstract
The membrane attack complex (MAC) is an important innate immune effector of the complement terminal pathway that forms cytotoxic pores on the surface of microbes. Despite many years of research, MAC structure and mechanism of action have remained elusive, relying heavily on modelling and inference from biochemical experiments. Recent advances in structural biology, specifically cryo-electron microscopy, have provided new insights into the molecular mechanism of MAC assembly. Its unique 'split-washer' shape, coupled with an irregular giant β-barrel architecture, enable an atypical mechanism of hole punching and represent a novel system for which to study pore formation. This review will introduce the complement terminal pathway that leads to formation of the MAC. Moreover, it will discuss how structures of the pore and component proteins underpin a mechanism for MAC function, modulation and inhibition.This article is part of the themed issue 'Membrane pores: from structure and assembly, to medicine and technology'.
Collapse
Affiliation(s)
- Charles Bayly-Jones
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton Campus, Melbourne, Victoria 3800, Australia
- ARC Centre of Excellence in Advanced Molecular Imaging, Biomedicine Discovery Institute, Monash University, Clayton Campus, Melbourne, Victoria 3800, Australia
| | - Doryen Bubeck
- Department of Life Sciences, Imperial College London, South Kensington Campus, London SW2 7AZ, UK
| | - Michelle A Dunstone
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton Campus, Melbourne, Victoria 3800, Australia
- ARC Centre of Excellence in Advanced Molecular Imaging, Biomedicine Discovery Institute, Monash University, Clayton Campus, Melbourne, Victoria 3800, Australia
| |
Collapse
|
20
|
Pedersen DV, Roumenina L, Jensen RK, Gadeberg TA, Marinozzi C, Picard C, Rybkine T, Thiel S, Sørensen UB, Stover C, Fremeaux-Bacchi V, Andersen GR. Functional and structural insight into properdin control of complement alternative pathway amplification. EMBO J 2017; 36:1084-1099. [PMID: 28264884 DOI: 10.15252/embj.201696173] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Revised: 01/16/2017] [Accepted: 01/31/2017] [Indexed: 12/22/2022] Open
Abstract
Properdin (FP) is an essential positive regulator of the complement alternative pathway (AP) providing stabilization of the C3 and C5 convertases, but its oligomeric nature challenges structural analysis. We describe here a novel FP deficiency (E244K) caused by a single point mutation which results in a very low level of AP activity. Recombinant FP E244K is monomeric, fails to support bacteriolysis, and binds weakly to C3 products. We compare this to a monomeric unit excised from oligomeric FP, which is also dysfunctional in bacteriolysis but binds the AP proconvertase, C3 convertase, C3 products and partially stabilizes the convertase. The crystal structure of such a FP-convertase complex suggests that the major contact between FP and the AP convertase is mediated by a single FP thrombospondin repeat and a small region in C3b. Small angle X-ray scattering indicates that FP E244K is trapped in a compact conformation preventing its oligomerization. Our studies demonstrate an essential role of FP oligomerization in vivo while our monomers enable detailed structural insight paving the way for novel modulators of complement.
Collapse
Affiliation(s)
- Dennis V Pedersen
- Department of Molecular Biology and Genetics, Center for Structural Biology, Aarhus University, Aarhus, Denmark
| | - Lubka Roumenina
- INSERM, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France.,Sorbonne Universités, UPMC Univ Paris 06, Paris, France.,Sorbonne Paris Cité, Université Paris Descartes, Paris, France
| | - Rasmus K Jensen
- Department of Molecular Biology and Genetics, Center for Structural Biology, Aarhus University, Aarhus, Denmark
| | - Trine Af Gadeberg
- Department of Molecular Biology and Genetics, Center for Structural Biology, Aarhus University, Aarhus, Denmark
| | - Chiara Marinozzi
- Assistance Publique - Hôpitaux de Paris, Service d'Immunologie Biologique, Hôpital Européen Georges Pompidou, Paris, France
| | - Capucine Picard
- Centre d'études des déficits immunitaires, CHU Paris - Hôpital Necker-Enfants Malades, Paris, France
| | - Tania Rybkine
- INSERM, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France.,Sorbonne Universités, UPMC Univ Paris 06, Paris, France.,Sorbonne Paris Cité, Université Paris Descartes, Paris, France
| | - Steffen Thiel
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | | | - Cordula Stover
- Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, UK
| | - Veronique Fremeaux-Bacchi
- INSERM, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France.,Sorbonne Universités, UPMC Univ Paris 06, Paris, France.,Sorbonne Paris Cité, Université Paris Descartes, Paris, France.,Assistance Publique - Hôpitaux de Paris, Service d'Immunologie Biologique, Hôpital Européen Georges Pompidou, Paris, France
| | - Gregers R Andersen
- Department of Molecular Biology and Genetics, Center for Structural Biology, Aarhus University, Aarhus, Denmark
| |
Collapse
|
21
|
EL-HALAWANY NERMIN, SHAWKY ABDELMONSIFA, M. AL-TOHAMY AHMEDF, HEGAZY LAMEES, ABDEL-SHAFY HAMDY, ABDEL-LATIF MAGDYA, GHAZI YASSERA, NEUHOFF CHRISTIANE, SALILEW-WONDIM DESSIE, SCHELLANDER KARL. Complement component 3: characterization and association with mastitis resistance in Egyptian water buffalo and cattle. J Genet 2017; 96:65-73. [DOI: 10.1007/s12041-017-0740-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
|
22
|
Abstract
α2-macroglobulins are broad-spectrum endopeptidase inhibitors, which have to date been characterised from metazoans (vertebrates and invertebrates) and Gram-negative bacteria. Their structural and biochemical properties reveal two related modes of action: the "Venus flytrap" and the "snap-trap" mechanisms. In both cases, peptidases trigger a massive conformational rearrangement of α2-macroglobulin after cutting in a highly flexible bait region, which results in their entrapment. In some homologs, a second action takes place that involves a highly reactive β-cysteinyl-γ-glutamyl thioester bond, which covalently binds cleaving peptidases and thus contributes to the further stabilization of the enzyme:inhibitor complex. Trapped peptidases are still active, but have restricted access to their substrates due to steric hindrance. In this way, the human α2-macroglobulin homolog regulates proteolysis in complex biological processes, such as nutrition, signalling, and tissue remodelling, but also defends the host organism against attacks by external toxins and other virulence factors during infection and envenomation. In parallel, it participates in several other biological functions by modifying the activity of cytokines and regulating hormones, growth factors, lipid factors and other proteins, which has a great impact on physiology. Likewise, bacterial α2-macroglobulins may participate in defence by protecting cell wall components from attacking peptidases, or in host-pathogen interactions through recognition of host peptidases and/or antimicrobial peptides. α2-macroglobulins are more widespread than initially thought and exert multifunctional roles in both eukaryotes and prokaryotes, therefore, their on-going study is essential.
Collapse
Affiliation(s)
- Irene Garcia-Ferrer
- Proteolysis Lab, Structural Biology Unit, "María de Maeztu" Unit of Excellence, Molecular Biology Institute of Barcelona (CSIC), Barcelona Science Park; c/Baldiri Reixac, 15-21, 08028, Barcelona, Spain
- Present address: EMBL Grenoble, 71 Avenue des Martyrs; 38042 CS 90181, Grenoble Cedex 9, France
| | - Aniebrys Marrero
- Proteolysis Lab, Structural Biology Unit, "María de Maeztu" Unit of Excellence, Molecular Biology Institute of Barcelona (CSIC), Barcelona Science Park; c/Baldiri Reixac, 15-21, 08028, Barcelona, Spain
- Present address: Department of Chemistry, University of Zürich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - F Xavier Gomis-Rüth
- Proteolysis Lab, Structural Biology Unit, "María de Maeztu" Unit of Excellence, Molecular Biology Institute of Barcelona (CSIC), Barcelona Science Park; c/Baldiri Reixac, 15-21, 08028, Barcelona, Spain
| | - Theodoros Goulas
- Proteolysis Lab, Structural Biology Unit, "María de Maeztu" Unit of Excellence, Molecular Biology Institute of Barcelona (CSIC), Barcelona Science Park; c/Baldiri Reixac, 15-21, 08028, Barcelona, Spain.
| |
Collapse
|
23
|
Li SQ, Feng L, Jiang WD, Liu Y, Jiang J, Wu P, Kuang SY, Tang L, Tang WN, Zhang YA, Zhou XQ. Deficiency of dietary niacin impaired gill immunity and antioxidant capacity, and changes its tight junction proteins via regulating NF-κB, TOR, Nrf2 and MLCK signaling pathways in young grass carp (Ctenopharyngodon idella). FISH & SHELLFISH IMMUNOLOGY 2016; 55:212-222. [PMID: 27181596 DOI: 10.1016/j.fsi.2016.05.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Revised: 04/12/2016] [Accepted: 05/05/2016] [Indexed: 06/05/2023]
Abstract
To investigate the effects of dietary niacin on gill immunity, tight junction proteins, antioxidant system and related signaling molecules mRNA expression, young grass carp (Ctenopharyngodon idella) were fed six diets containing graded levels of niacin (3.95-55.01 mg/kg diet) for 8 weeks. The study indicated that niacin deficiency decreased lysozyme and acid phosphatase activities, and complement 3 content, and caused oxidative damage that might be partly due to the decreased copper, zinc superoxide dismutase, catalase, glutathione reductase, glutathione peroxidase and glutathione-S-transferase activities and reduced glutathione content in fish gills (P < 0.05). Moreover, the relative mRNA levels of antimicrobial peptides (liver expressed antimicrobial peptide 2 and Hepcidin), anti-inflammatory cytokines (interleukin 10 and transforming growth factor β1), tight junction proteins (Occludin, zonula occludens 1, Claudin-15 and -3), signaling molecules (inhibitor of κBα (IκBα), target of rapamycin (TOR), ribosomal protein S6 kinase 1 (S6K1) and NF-E2-related factor 2 (Nrf2)) and antioxidant enzymes were significantly decreased (P < 0.05) in niacin-deficient diet group. Conversely, the mRNA levels of pro-inflammatory cytokines (tumor necrosis factor α, interleukin 8, interferon γ2, and interleukin 1β), signaling molecules (nuclear factor kappa B p65, IκB kinase α, IκB kinase β, IκB kinase γ, Kelch-like-ECH-associated protein 1b, myosin light chain kinase and p38 mitogen-activated protein kinase (p38 MAPK) were significantly increased (P < 0.05) in fish gills fed niacin-deficient diet. Interestingly, the varying niacin levels of 3.95-55.01 mg/kg diet had no effect on the mRNA level of Kelch-like-ECH-associated protein 1a, Claudin-c and -12 in fish gills (P > 0.05). In conclusion, niacin deficiency decreased gill immunity, impaired gill antioxidant system, as well as regulated mRNA expression of gill tight junction proteins and related signaling molecules of fish.
Collapse
Affiliation(s)
- Shun-Quan Li
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, 611130, China
| | - Lin Feng
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, 611130, China; Fish Nutrition and Safety Production University Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, 611130, China; Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Sichuan Agricultural University, Chengdu, 611130, China
| | - Wei-Dan Jiang
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, 611130, China; Fish Nutrition and Safety Production University Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, 611130, China; Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Sichuan Agricultural University, Chengdu, 611130, China
| | - Yang Liu
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, 611130, China; Fish Nutrition and Safety Production University Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, 611130, China; Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Sichuan Agricultural University, Chengdu, 611130, China
| | - Jun Jiang
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, 611130, China; Fish Nutrition and Safety Production University Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, 611130, China; Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Sichuan Agricultural University, Chengdu, 611130, China
| | - Pei Wu
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, 611130, China; Fish Nutrition and Safety Production University Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, 611130, China; Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Sichuan Agricultural University, Chengdu, 611130, China
| | - Sheng-Yao Kuang
- Animal Nutrition Institute, Sichuan Academy of Animal Science, Chengdu, 610066, China
| | - Ling Tang
- Animal Nutrition Institute, Sichuan Academy of Animal Science, Chengdu, 610066, China
| | - Wu-Neng Tang
- Animal Nutrition Institute, Sichuan Academy of Animal Science, Chengdu, 610066, China
| | - Yong-An Zhang
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Xiao-Qiu Zhou
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, 611130, China; Fish Nutrition and Safety Production University Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, 611130, China; Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Sichuan Agricultural University, Chengdu, 611130, China.
| |
Collapse
|
24
|
Forneris F, Wu J, Xue X, Ricklin D, Lin Z, Sfyroera G, Tzekou A, Volokhina E, Granneman JC, Hauhart R, Bertram P, Liszewski MK, Atkinson JP, Lambris JD, Gros P. Regulators of complement activity mediate inhibitory mechanisms through a common C3b-binding mode. EMBO J 2016; 35:1133-49. [PMID: 27013439 PMCID: PMC4868954 DOI: 10.15252/embj.201593673] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Accepted: 02/29/2016] [Indexed: 01/17/2023] Open
Abstract
Regulators of complement activation (RCA) inhibit complement‐induced immune responses on healthy host tissues. We present crystal structures of human RCA (MCP, DAF, and CR1) and a smallpox virus homolog (SPICE) bound to complement component C3b. Our structural data reveal that up to four consecutive homologous CCP domains (i–iv), responsible for inhibition, bind in the same orientation and extended arrangement at a shared binding platform on C3b. Large sequence variations in CCP domains explain the diverse C3b‐binding patterns, with limited or no contribution of some individual domains, while all regulators show extensive contacts with C3b for the domains at the third site. A variation of ~100° rotation around the longitudinal axis is observed for domains binding at the fourth site on C3b, without affecting the overall binding mode. The data suggest a common evolutionary origin for both inhibitory mechanisms, called decay acceleration and cofactor activity, with variable C3b binding through domains at sites ii, iii, and iv, and provide a framework for understanding RCA disease‐related mutations and immune evasion.
Collapse
Affiliation(s)
- Federico Forneris
- Crystal and Structural Chemistry, Bijvoet Center for Biomolecular Research, Department of Chemistry, Faculty of Science Utrecht University, Utrecht, The Netherlands
| | - Jin Wu
- Crystal and Structural Chemistry, Bijvoet Center for Biomolecular Research, Department of Chemistry, Faculty of Science Utrecht University, Utrecht, The Netherlands
| | - Xiaoguang Xue
- Crystal and Structural Chemistry, Bijvoet Center for Biomolecular Research, Department of Chemistry, Faculty of Science Utrecht University, Utrecht, The Netherlands
| | - Daniel Ricklin
- Department of Pathology & Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Zhuoer Lin
- Department of Pathology & Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Georgia Sfyroera
- Department of Pathology & Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Apostolia Tzekou
- Department of Pathology & Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Elena Volokhina
- Department of Pediatric Nephrology (830), Radboud University Medical Center, Nijmegen, The Netherlands
| | - Joke Cm Granneman
- Crystal and Structural Chemistry, Bijvoet Center for Biomolecular Research, Department of Chemistry, Faculty of Science Utrecht University, Utrecht, The Netherlands
| | - Richard Hauhart
- Department of Medicine, Division of Rheumatology, Washington University School of Medicine, St. Louis, MO, USA
| | - Paula Bertram
- Department of Medicine, Division of Rheumatology, Washington University School of Medicine, St. Louis, MO, USA
| | - M Kathryn Liszewski
- Department of Medicine, Division of Rheumatology, Washington University School of Medicine, St. Louis, MO, USA
| | - John P Atkinson
- Department of Medicine, Division of Rheumatology, Washington University School of Medicine, St. Louis, MO, USA
| | - John D Lambris
- Department of Pathology & Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Piet Gros
- Crystal and Structural Chemistry, Bijvoet Center for Biomolecular Research, Department of Chemistry, Faculty of Science Utrecht University, Utrecht, The Netherlands
| |
Collapse
|
25
|
Feng L, Li SQ, Jiang WD, Liu Y, Jiang J, Wu P, Zhao J, Kuang SY, Tang L, Tang WN, Zhang YA, Zhou XQ. Deficiency of dietary niacin impaired intestinal mucosal immune function via regulating intestinal NF-κB, Nrf2 and MLCK signaling pathways in young grass carp (Ctenopharyngodon idella). FISH & SHELLFISH IMMUNOLOGY 2016; 49:177-193. [PMID: 26693667 DOI: 10.1016/j.fsi.2015.12.015] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 12/10/2015] [Accepted: 12/12/2015] [Indexed: 06/05/2023]
Abstract
This study investigated the effects of dietary niacin on intestinal mucosal immune and physical barrier, and relative mRNA levels of signaling molecules in the intestine of young grass carp (Ctenopharyngodon idella). A total of 540 young grass carp (255.63 ± 0.41 g) were fed six diets containing graded levels of niacin (3.95, 14.92, 24.98, 35.03, 44.97 and 55.01 mg/kg diet) for 8 weeks. Results observed that niacin deficiency decreased lysozyme (LA) and acid phosphatase (ACP) activities, and complement 3 (C3) content in the intestine (P < 0.05), down-regulated mRNA levels of liver expressed antimicrobial peptide 2 (LEAP-2), hepcidin, interleukin 10, transforming growth factor β1 and inhibitor of κBα (IκBα) (P < 0.05), up-regulated tumor necrosis factor α, interleukin 1β, interferon γ2, interleukin 8, nuclear factor kappa B P65 (NF-κB P65), IκB kinase α (IKKα), IκB kinase β (IKKβ) and IκB kinase γ (IKKγ) in all intestinal segments of young grass carp (P < 0.05). In addition, niacin deficiency increased reactive oxygen species (ROS), malondialdehyde (MDA) and protein carbonyl (PC) contents, decreased glutathione content, and copper/zinc superoxide dismutase (CuZnSOD), manganese superoxide dismutase (MnSOD), catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferases (GST) and glutathione reductase (GR) activities in the intestine of young grass carp (P < 0.05). Additionally, niacin deficiency decreased mRNA levels of CuZnSOD, MnSOD, GPx, CAT, GST, GR, Claudin b, Claudin 3, Claudin c, Occludin, ZO-1, Claudin 15 and NF-E2-related factor 2 (Nrf2) (P < 0.05), and increased Claudin 12, Kelch-like ECH-associating protein 1a (Keap1a), myosin light-chain kinase (MLCK) and p38 mitogen-activated protein kinase (p38 MAPK) mRNA expression levels in the intestine of young grass carp (P < 0.05), while the mRNA level of Kelch-like ECH-associating protein 1b (Keap1b) did not change (P > 0.05). In conclusion, niacin deficiency decreased intestinal mucosal immune and intestinal physical function, as well as regulated mRNA levels of NF-κB P65, IκBα, IKKα, IKKβ, IKKγ, Nrf2, Keap1a, p38 MAPK and MLCK in the intestine of young grass carp. Based on the broken-line model analysis of intestinal lysozyme activity, the requirement of niacin for young grass carp (255.63 ± 0.41 g) were estimated to be 39.80 mg/kg diet.
Collapse
Affiliation(s)
- Lin Feng
- Animal Nutrition Institute, Sichuan Agricultural University, Sichuan, Chengdu, 611130, Sichuan, China; Fish Nutrition and Safety Production University Key Laboratory of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China; Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
| | - Shun-Quan Li
- Animal Nutrition Institute, Sichuan Agricultural University, Sichuan, Chengdu, 611130, Sichuan, China
| | - Wei-Dan Jiang
- Animal Nutrition Institute, Sichuan Agricultural University, Sichuan, Chengdu, 611130, Sichuan, China; Fish Nutrition and Safety Production University Key Laboratory of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China; Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
| | - Yang Liu
- Animal Nutrition Institute, Sichuan Agricultural University, Sichuan, Chengdu, 611130, Sichuan, China; Fish Nutrition and Safety Production University Key Laboratory of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China; Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
| | - Jun Jiang
- Animal Nutrition Institute, Sichuan Agricultural University, Sichuan, Chengdu, 611130, Sichuan, China; Fish Nutrition and Safety Production University Key Laboratory of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China; Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
| | - Pei Wu
- Animal Nutrition Institute, Sichuan Agricultural University, Sichuan, Chengdu, 611130, Sichuan, China; Fish Nutrition and Safety Production University Key Laboratory of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China; Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
| | - Juan Zhao
- Animal Nutrition Institute, Sichuan Agricultural University, Sichuan, Chengdu, 611130, Sichuan, China; Fish Nutrition and Safety Production University Key Laboratory of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China; Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
| | - Sheng-Yao Kuang
- Animal Nutrition Institute, Sichuan Academy of Animal Science, Chengdu, 610066, Sichuan, China
| | - Ling Tang
- Animal Nutrition Institute, Sichuan Academy of Animal Science, Chengdu, 610066, Sichuan, China
| | - Wu-Neng Tang
- Animal Nutrition Institute, Sichuan Academy of Animal Science, Chengdu, 610066, Sichuan, China
| | - Yong-An Zhang
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Xiao-Qiu Zhou
- Animal Nutrition Institute, Sichuan Agricultural University, Sichuan, Chengdu, 611130, Sichuan, China; Fish Nutrition and Safety Production University Key Laboratory of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China; Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.
| |
Collapse
|
26
|
Acute-phase protein behavior in dairy cattle herd naturally infected with Trypanosoma vivax. Vet Parasitol 2015; 211:141-5. [DOI: 10.1016/j.vetpar.2015.05.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Revised: 05/12/2015] [Accepted: 05/13/2015] [Indexed: 11/24/2022]
|
27
|
Melillo D, Varriale S, Giacomelli S, Natale L, Bargelloni L, Oreste U, Pinto MR, Coscia MR. Evolution of the complement system C3 gene in Antarctic teleosts. Mol Immunol 2015; 66:299-309. [PMID: 25909494 DOI: 10.1016/j.molimm.2015.03.247] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Revised: 03/16/2015] [Accepted: 03/18/2015] [Indexed: 11/29/2022]
Abstract
Notothenioidei are typical Antarctic teleosts evolved to adapt to the very low temperatures of the Antarctic seas. Aim of the present paper is to investigate sequence and structure of C3, the third component of the complement system of the notothenioid Trematomus bernacchii and Chionodraco hamatus. We determined the complete nucleotide sequence of two C3 isoforms of T. bernacchii and a single C3 isoform of C. hamatus. These sequences were aligned against other homologous teleost sequences to check for the presence of diversifying selection. Evidence for positive selection was observed in the evolutionary lineage of Antarctic teleost C3 sequences, especially in that of C. hamatus, the most recently diverged species. Adaptive selection affected numerous amino acid positions including three residues located in the anaphylatoxin domain. In an attempt to evaluate the link between sequence variants and specific structural features, we constructed molecular models of Antarctic teleost C3s, of their proteolytic fragments C3b and C3a, and of the corresponding molecules of the phylogenetically related temperate species Epinephelus coioides, using human crystallographic structures as templates. Subsequently, we compared dynamic features of these models by molecular dynamics simulations and found that the Antarctic C3s models show higher flexibility, which likely allows for more pronounced movements of both the TED domain in C3b and the carboxyl-terminal region of C3a. As such dynamic features are associated to positively selected sites, it appears that Antarctic teleost C3 molecules positively evolved toward an increased flexibility, to cope with low kinetic energy levels of the Antarctic marine environment.
Collapse
Affiliation(s)
- Daniela Melillo
- Department of Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Napoli (SZN), Italy
| | - Sonia Varriale
- Institute of Protein Biochemistry, CNR, Via Pietro Castellino 111, 80131 Napoli, Italy
| | - Stefano Giacomelli
- Institute of Protein Biochemistry, CNR, Via Pietro Castellino 111, 80131 Napoli, Italy
| | - Lenina Natale
- Department of Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Napoli (SZN), Italy
| | - Luca Bargelloni
- Department of Comparative Biomedicine and Food Science, University of Padua, Via Ugo Bassi 58/B, 35131 Padova, Italy
| | - Umberto Oreste
- Institute of Protein Biochemistry, CNR, Via Pietro Castellino 111, 80131 Napoli, Italy
| | - Maria Rosaria Pinto
- Department of Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Napoli (SZN), Italy
| | - Maria Rosaria Coscia
- Institute of Protein Biochemistry, CNR, Via Pietro Castellino 111, 80131 Napoli, Italy.
| |
Collapse
|
28
|
Rodriguez E, Nan R, Li K, Gor J, Perkins SJ. A revised mechanism for the activation of complement C3 to C3b: a molecular explanation of a disease-associated polymorphism. J Biol Chem 2015; 290:2334-50. [PMID: 25488663 PMCID: PMC4303685 DOI: 10.1074/jbc.m114.605691] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Revised: 11/28/2014] [Indexed: 11/06/2022] Open
Abstract
The solution structure of complement C3b is crucial for the understanding of complement activation and regulation. C3b is generated by the removal of C3a from C3. Hydrolysis of the C3 thioester produces C3u, an analog of C3b. C3b cleavage results in C3c and C3d (thioester-containing domain; TED). To resolve functional questions in relation to C3b and C3u, analytical ultracentrifugation and x-ray and neutron scattering studies were used with C3, C3b, C3u, C3c, and C3d, using the wild-type allotype with Arg(102). In 50 mm NaCl buffer, atomistic scattering modeling showed that both C3b and C3u adopted a compact structure, similar to the C3b crystal structure in which its TED and macroglobulin 1 (MG1) domains were connected through the Arg(102)-Glu(1032) salt bridge. In physiological 137 mm NaCl, scattering modeling showed that C3b and C3u were both extended in structure, with the TED and MG1 domains now separated by up to 6 nm. The importance of the Arg(102)-Glu(1032) salt bridge was determined using surface plasmon resonance to monitor the binding of wild-type C3d(E1032) and mutant C3d(A1032) to immobilized C3c. The mutant did not bind, whereas the wild-type form did. The high conformational variability of TED in C3b in physiological buffer showed that C3b is more reactive than previously thought. Because the Arg(102)-Glu(1032) salt bridge is essential for the C3b-Factor H complex during the regulatory control of C3b, the known clinical associations of the major C3S (Arg(102)) and disease-linked C3F (Gly(102)) allotypes of C3b were experimentally explained for the first time.
Collapse
Affiliation(s)
- Elizabeth Rodriguez
- From the Department of Structural and Molecular Biology, Division of Biosciences, Darwin Building, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - Ruodan Nan
- From the Department of Structural and Molecular Biology, Division of Biosciences, Darwin Building, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - Keying Li
- From the Department of Structural and Molecular Biology, Division of Biosciences, Darwin Building, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - Jayesh Gor
- From the Department of Structural and Molecular Biology, Division of Biosciences, Darwin Building, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - Stephen J Perkins
- From the Department of Structural and Molecular Biology, Division of Biosciences, Darwin Building, University College London, Gower Street, London WC1E 6BT, United Kingdom
| |
Collapse
|
29
|
Williams M, Baxter R. The structure and function of thioester-containing proteins in arthropods. Biophys Rev 2014; 6:261-272. [PMID: 28510031 DOI: 10.1007/s12551-014-0142-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Accepted: 06/19/2014] [Indexed: 10/25/2022] Open
Abstract
Thioester-containing proteins (TEPs) form an ancient and diverse family of secreted proteins that play central roles in the innate immune response. Two families of TEPs, complement factors and α2-macroglobulins, have been known and studied in vertebrates for many years, but only in the last decade have crystal structures become available. In the same period, the presence of two additional classes of TEPs has been revealed in arthropods. In this review, we discuss the common structural features TEPs and how this knowledge can be applied to the many arthropod TEPs of unknown function. TEPs perform a wide variety of functions that are driven by different quaternary structures and protein-protein interactions between a common set of folded domains. A common theme is regulated conformational change triggered by proteolysis. Structure-function analysis of the diverse arthropod TEPs may identify not just new mechanisms in innate immunity but also interfaces between immunity, development and cell death.
Collapse
Affiliation(s)
- Marni Williams
- Department. of Chemistry, Yale University, New Haven, CT, USA
| | - Richard Baxter
- Department. of Chemistry, Yale University, New Haven, CT, USA.
| |
Collapse
|
30
|
Abstract
The complement system is an intricate network of serum proteins that mediates humoral innate immunity through an amplification cascade that ultimately leads to recruitment of inflammatory cells or opsonisation or killing of pathogens. One effector arm of this network is the terminal pathway of complement, which leads to the formation of the membrane attack complex (MAC) composed of complement components C5b, C6, C7, C8 and C9. Upon formation of C5 convertases via the classical or alternative pathways of complement activation, C5b is generated from C5 by proteolytic cleavage, nucleating a series of association and polymerisation reactions of the MAC-constituting complement components that culminate in pore formation of pathogenic membranes. Recent structures of MAC components and homologous proteins significantly increased our understanding of oligomerisation, membrane association and integration, shedding light onto the molecular mechanism of this important branch of the innate immune system.
Collapse
|
31
|
Matsubara T, Sasamoto C. Computational Study of the Binding Mechanism of Complement C3b with Antigen. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2013. [DOI: 10.1246/bcsj.20130181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
| | - Chisato Sasamoto
- Department of Chemistry, Faculty of Science, Kanagawa University
| |
Collapse
|
32
|
Structural insight on the recognition of surface-bound opsonins by the integrin I domain of complement receptor 3. Proc Natl Acad Sci U S A 2013; 110:16426-31. [PMID: 24065820 DOI: 10.1073/pnas.1311261110] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Complement receptors (CRs), expressed notably on myeloid and lymphoid cells, play an essential function in the elimination of complement-opsonized pathogens and apoptotic/necrotic cells. In addition, these receptors are crucial for the cross-talk between the innate and adaptive branches of the immune system. CR3 (also known as Mac-1, integrin αMβ2, or CD11b/CD18) is expressed on all macrophages and recognizes iC3b on complement-opsonized objects, enabling their phagocytosis. We demonstrate that the C3d moiety of iC3b harbors the binding site for the CR3 αI domain, and our structure of the C3d:αI domain complex rationalizes the CR3 selectivity for iC3b. Based on extensive structural analysis, we suggest that the choice between a ligand glutamate or aspartate for coordination of a receptor metal ion-dependent adhesion site-bound metal ion is governed by the secondary structure of the ligand. Comparison of our structure to the CR2:C3d complex and the in vitro formation of a stable CR3:C3d:CR2 complex suggests a molecular mechanism for the hand-over of CR3-bound immune complexes from macrophages to CR2-presenting cells in lymph nodes.
Collapse
|
33
|
Brodersen DE, Andersen GR, Andersen CBF. Mimer: an automated spreadsheet-based crystallization screening system. Acta Crystallogr Sect F Struct Biol Cryst Commun 2013; 69:815-20. [PMID: 23832216 DOI: 10.1107/s1744309113014425] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Accepted: 05/24/2013] [Indexed: 11/10/2022]
Abstract
In this paper, a simple low-cost alternative to large commercial systems for preparing macromolecular crystallization conditions is described. Using an intuitive spreadsheet-based approach, the system allows the rapid calculation of relevant pipetting volumes given known stock-solution concentrations and incorporates the automatic design of custom crystallization screens via the incomplete-factorial and grid-screen approaches. Automated dispensing of the resulting crystallization screens is achieved using a generic and relatively inexpensive liquid handler.
Collapse
Affiliation(s)
- Ditlev Egeskov Brodersen
- Department of Molecular Biology and Genetics, Aarhus University, Gustav Wieds Vej 10c, DK-8000 Aarhus C, Denmark.
| | | | | |
Collapse
|
34
|
Rehman AA, Ahsan H, Khan FH. α-2-Macroglobulin: a physiological guardian. J Cell Physiol 2013; 228:1665-75. [PMID: 23086799 DOI: 10.1002/jcp.24266] [Citation(s) in RCA: 240] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Accepted: 10/12/2012] [Indexed: 12/18/2022]
Abstract
Alpha macroglobulins are large glycoproteins which are present in the body fluids of both invertebrates and vertebrates. Alpha-2-macroglobulin (α2 M), a key member of alpha macroglobulin superfamily, is a high-molecular weight homotetrameric glycoprotein. α2 M has many diversified and complex functions, but it is primarily known by its ability to inhibit a broad spectrum of proteases without the direct blockage of the protease active site. α2 M is also known to be involved in the regulation, transport, and a host of other functions. For example, apart from inhibiting proteinases, it regulates binding of transferrin to its surface receptor, binds defensin and myelin basic protein, etc., binds several important cytokines, including basic fibroblast growth factor (bFGF), platelet-derived growth factor (PDGF), nerve growth factor (NGF), interleukin-1β (IL-1β), and interleukin-6 (IL-6), and modify their biological activity. α2 M also binds a number of hormones and regulates their activity. α2 M is said to protect the body against various infections, and hence, can be used as a biomarker for the diagnosis and prognosis of a number of diseases. However, this multipurpose antiproteinse is not "fail safe" and could be damaged by reactive species generated endogenously or exogenously, leading to various pathophysiological conditions.
Collapse
Affiliation(s)
- Ahmed A Rehman
- Faculty of Life Sciences, Department of Biochemistry, Aligarh Muslim University, Aligarh, India
| | | | | |
Collapse
|
35
|
Riedel T, Riedelová-Reicheltová Z, Májek P, Rodriguez-Emmenegger C, Houska M, Dyr JE, Brynda E. Complete identification of proteins responsible for human blood plasma fouling on poly(ethylene glycol)-based surfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:3388-3397. [PMID: 23391268 DOI: 10.1021/la304886r] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The resistance of poly(ethylene glycol) (PEG) against protein adsorption is crucial and has been widely utilized in various biomedical applications. In this work, the complete protein composition of biofilms deposited on PEG-based surfaces from human blood plasma (BP) was identified for the first time using nanoLC-MS/MS, a powerful tool in protein analysis. The mass of deposited BP and the number of different proteins contained in the deposits on individual surfaces decreased in the order of self-assembling monolayers of oligo(ethylene glycol) alkanethiolates (SAM) > poly(ethylene glycol) end-grafted onto a SAM > poly(oligo(ethylene glycol) methacrylate) brushes prepared by surface initiated polymerization (poly(OEGMA)). The BP deposit on the poly(OEGMA) surface was composed only of apolipoprotein A-I, apolipoprotein B-100, complement C3, complement C4-A, complement C4-B, histidine-rich glycoprotein, Ig mu chain C region, fibrinogen (Fbg), and serum albumin (HSA). The total resistance of the surface to the Fbg and HSA adsorption from single protein solutions suggested that their deposition from BP was mediated by some of the other proteins. Current theories of protein resistance are not sufficient to explain the observed plasma fouling. The research focused on the identified proteins, and the experimental approach used in this work can provide the basis for the understanding and rational design of plasma-resistant surfaces.
Collapse
Affiliation(s)
- Tomáš Riedel
- Department of Biomaterials and Bioanalogous Systems, Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, vvi, Prague, Czech Republic
| | | | | | | | | | | | | |
Collapse
|
36
|
Bajic G, Yatime L, Klos A, Andersen GR. Human C3a and C3a desArg anaphylatoxins have conserved structures, in contrast to C5a and C5a desArg. Protein Sci 2012. [PMID: 23184394 DOI: 10.1002/pro.2200] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Complement is a part of innate immunity that has a critical role in the protection against microbial infections, bridges the innate with the adaptive immunity and initiates inflammation. Activation of the complement, by specific recognition of molecular patterns presented by an activator, for example, a pathogen cell, in the classical and lectin pathways or spontaneously in the alternative pathway, leads to the opsonization of the activator and the production of pro-inflammatory molecules such as the C3a anaphylatoxin. The biological function of this anaphylatoxin is regulated by carboxypeptidase B, a plasma protease that cleaves off the C-terminal arginine yielding C3a desArg, an inactive form. While functional assays demonstrate strikingly different physiological effects between C3a and C3a desArg, no structural information is available on the possible conformational differences between the two proteins. Here, we report a novel and simple expression and purification protocol for recombinant human C3a and C3a desArg anaphylatoxins, as well as their crystal structures at 2.3 and 2.6 Å, respectively. Structural analysis revealed no significant conformational differences between the two anaphylatoxins in contrast to what has been reported for C5a and C5a desArg. We compare the structures of different anaphylatoxins and discuss the relevance of their observed conformations to complement activation and binding of the anaphylatoxins to their cognate receptors.
Collapse
Affiliation(s)
- Goran Bajic
- Department of Molecular Biology and Genetics, Aarhus University, Gustav Wieds Vej 10C, DK-8000 Aarhus, Denmark
| | | | | | | |
Collapse
|
37
|
Fischer K, Da Costa LA, García-Bailo B, Borchers CH, El-Sohemy A. Glutathione S-Transferase (GST) M1, but Not GSTT1, Genotype Influences Plasma Proteomic Profiles in Caucasian and East Asian Young Adults. J Proteome Res 2012; 11:5022-33. [DOI: 10.1021/pr3005887] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Karina Fischer
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario M5S 3E2, Canada
- Institute of Food, Nutrition
and Health, Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
| | - Laura A. Da Costa
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario M5S 3E2, Canada
| | - Bibiana García-Bailo
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario M5S 3E2, Canada
| | - Christoph H. Borchers
- University of Victoria-Genome British Columbia
Proteomics Centre, University of Victoria, Victoria, British Columbia, Canada
| | - Ahmed El-Sohemy
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario M5S 3E2, Canada
| |
Collapse
|
38
|
Structural basis for activation of the complement system by component C4 cleavage. Proc Natl Acad Sci U S A 2012; 109:15425-30. [PMID: 22949645 DOI: 10.1073/pnas.1208031109] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
An essential aspect of innate immunity is recognition of molecular patterns on the surface of pathogens or altered self through the lectin and classical pathways, two of the three well-established activation pathways of the complement system. This recognition causes activation of the MASP-2 or the C1s serine proteases followed by cleavage of the protein C4. Here we present the crystal structures of the 203-kDa human C4 and the 245-kDa C4·MASP-2 substrate·enzyme complex. When C4 binds to MASP-2, substantial conformational changes in C4 are induced, and its scissile bond region becomes ordered and inserted into the protease catalytic site in a manner canonical to serine proteases. In MASP-2, an exosite located within the CCP domains recognizes the C4 C345C domain 60 Å from the scissile bond. Mutations in C4 and MASP-2 residues at the C345C-CCP interface inhibit the intermolecular interaction and C4 cleavage. The possible assembly of the huge in vivo enzyme-substrate complex consisting of glycan-bound mannan-binding lectin, MASP-2, and C4 is discussed. Our own and prior functional data suggest that C1s in the classical pathway of complement activated by, e.g., antigen-antibody complexes, also recognizes the C4 C345C domain through a CCP exosite. Our results provide a unified structural framework for understanding the early and essential step of C4 cleavage in the elimination of pathogens and altered self through two major pathways of complement activation.
Collapse
|
39
|
Yadav VN, Pyaram K, Ahmad M, Sahu A. Species selectivity in poxviral complement regulators is dictated by the charge reversal in the central complement control protein modules. THE JOURNAL OF IMMUNOLOGY 2012; 189:1431-9. [PMID: 22732591 DOI: 10.4049/jimmunol.1200946] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Variola and vaccinia viruses, the two most important members of the family Poxviridae, are known to encode homologs of the human complement regulators named smallpox inhibitor of complement enzymes (SPICE) and vaccinia virus complement control protein (VCP), respectively, to subvert the host complement system. Intriguingly, consistent with the host tropism of these viruses, SPICE has been shown to be more human complement-specific than VCP, and in this study we show that VCP is more bovine complement-specific than SPICE. Based on mutagenesis and mechanistic studies, we suggest that the major determinant for the switch in species selectivity of SPICE and VCP is the presence of oppositely charged residues in the central complement control modules, which help enhance their interaction with factor I and C3b, the proteolytically cleaved form of C3. Thus, our results provide a molecular basis for the species selectivity in poxviral complement regulators.
Collapse
Affiliation(s)
- Viveka Nand Yadav
- National Centre for Cell Science, Pune University, Ganeshkhind, Pune 411007, India
| | | | | | | |
Collapse
|
40
|
Forneris F, Wu J, Gros P. The modular serine proteases of the complement cascade. Curr Opin Struct Biol 2012; 22:333-41. [PMID: 22560446 DOI: 10.1016/j.sbi.2012.04.001] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Accepted: 04/05/2012] [Indexed: 11/30/2022]
Abstract
Modular serine proteases are central to the complement cascade of the mammalian humoral immune system. These proteases form protein complexes through multi-domain interactions to achieve their proteolytic activity. We review the structural insights into complement initiation by auto-activation of the hetero-tetrameric proteases of the large danger-recognition protein complexes, amplification and labelling of particles by the formation and activity of C3 convertases, and regulation by convertase dissociation and degradation to prevent 'bystander' damage to healthy host cells and tissues. The data reveal that complex formation and large domain-domain rearrangements underlie the proteolytic reactions of the complement cascade, which enables the host to recognize and clear invading microbes and host debris from its blood and fluids surrounding tissues.
Collapse
Affiliation(s)
- Federico Forneris
- Crystal and Structural Chemistry, Bijvoet Center for Biomolecular Research, Department of Chemistry, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | | | | |
Collapse
|
41
|
Neves D, Estrozi LF, Job V, Gabel F, Schoehn G, Dessen A. Conformational states of a bacterial α2-macroglobulin resemble those of human complement C3. PLoS One 2012; 7:e35384. [PMID: 22530012 PMCID: PMC3328433 DOI: 10.1371/journal.pone.0035384] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2011] [Accepted: 03/16/2012] [Indexed: 01/09/2023] Open
Abstract
α(2) macroglobulins (α(2)Ms) are broad-spectrum protease inhibitors that play essential roles in the innate immune system of eukaryotic species. These large, multi-domain proteins are characterized by a broad-spectrum bait region and an internal thioester, which, upon cleavage, becomes covalently associated to the target protease, allowing its entrapment by a large conformational modification. Notably, α(2)Ms are part of a larger protein superfamily that includes proteins of the complement system, such as C3, a multi-domain macromolecule which is also characterized by an internal thioester-carrying domain and whose activation represents the pivotal step in the complement cascade. Recently, α(2)M/C3-like genes were identified in a large number of bacterial genomes, and the Escherichia coli α(2)M homolog (ECAM) was shown to be activated by proteases. In this work, we have structurally characterized ECAM by electron microscopy and small angle scattering (SAXS) techniques. ECAM is an elongated, flexible molecule with overall similarities to C3 in its inactive form; activation by methylamine, chymotrypsin, or elastase induces a conformational modification reminiscent of the one undergone by the transformation of C3 into its active form, C3b. In addition, the proposed C-terminus of ECAM displays high flexibility and different conformations, and could be the recognition site for partner macromolecules. This work sheds light on a potential bacterial defense mechanism that mimics structural rearrangements essential for activation of the complement cascade in eukaryotes, and represents a possible novel target for the development of antibacterials.
Collapse
Affiliation(s)
- David Neves
- Institut de Biologie Structurale, Université Grenoble I, Grenoble, France.
| | | | | | | | | | | |
Collapse
|
42
|
Zhang LR, Liu ZJ, Zhang H, Sun J, Luo Y, Zhao TT, Gong HB, Zhu HL. Synthesis, biological evaluation and molecular docking studies of novel 2-(1,3,4-oxadiazol-2-ylthio)-1-phenylethanone derivatives. Bioorg Med Chem 2012; 20:3615-21. [PMID: 22541051 DOI: 10.1016/j.bmc.2012.03.061] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Revised: 03/27/2012] [Accepted: 03/27/2012] [Indexed: 10/28/2022]
Abstract
In present study, a series of new 2-(1,3,4-oxadiazol-2-ylthio)-1-phenylethanone derivatives (6a-6x) as potential focal adhesion kinase (FAK) inhibitors were synthesized. The bioassay assays demonstrated that compound 6i showed the most potent activity, which inhibited the growth of MCF-7 and A431 cell lines with IC(50) values of 140 ± 10 nM and 10 ± 1 nM, respectively. Compound 6i also exhibited significant FAK inhibitory activity (IC(50)=20 ± 1 nM). Docking simulation was performed to position compound 6i into the active site of FAK to determine the probable binding model.
Collapse
Affiliation(s)
- Li-Rong Zhang
- State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210093, PR China
| | | | | | | | | | | | | | | |
Collapse
|
43
|
Protein ultrastructure and the nanoscience of complement activation. Adv Drug Deliv Rev 2011; 63:1008-19. [PMID: 21699938 DOI: 10.1016/j.addr.2011.05.023] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2011] [Accepted: 05/31/2011] [Indexed: 12/24/2022]
Abstract
The complement system constitutes an important barrier to infection of the human body. Over more than four decades structural properties of the proteins of the complement system have been investigated with X-ray crystallography, electron microscopy, small-angle scattering, and atomic force microscopy. Here, we review the accumulated evidence that the nm-scaled dimensions and conformational changes of these proteins support functions of the complement system with regard to tissue distribution, molecular crowding effects, avidity binding, and conformational regulation of complement activation. In the targeting of complement activation to the surfaces of nanoparticulate material, such as engineered nanoparticles or fragments of the microbial cell wall, these processes play intimately together. This way the complement system is an excellent example where nanoscience may serve to unravel the molecular biology of the immune response.
Collapse
|
44
|
Holm L, Ackland GL, Edwards MR, Breckenridge RA, Sim RB, Offer J. Chemical labelling of active serum thioester proteins for quantification. Immunobiology 2011; 217:256-64. [PMID: 21852021 PMCID: PMC3274692 DOI: 10.1016/j.imbio.2011.07.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2011] [Revised: 07/08/2011] [Accepted: 07/18/2011] [Indexed: 11/19/2022]
Abstract
The complement serum proteins C3 and C4 and the protease inhibitor α-2 macroglobulin are all members of the C3/α-2M thioester protein family, an evolutionarily ancient and conserved family that contains an intrachain thioester bond. The chemistry of the thioester bond is a key to the function of the thioester proteins. All these proteins function by covalently linking to their target by acyl transfer of the protein via the thioester moiety. We show that the signature thioester bond can be targeted with nucleophiles linked to a bioreporter molecule, site-specifically modifying the whole, intact thioester protein. Conditions were optimised to label selectively and efficiently pull-down unprocessed thioester-containing proteins from serum. We demonstrated pull-down of full-length C3, α-2M and C4 from sera in high salt, using a biotinylated nucleophile and streptavidin-coated resin, confirmed by MALDI-TOF MS identification of the gel bands. The potential for the development of a quantitative method for measuring active C3 in serum was investigated in patient sera pre and post operation. Quantifying active C3 in clinical assays using current methods is difficult. Methods based on antibody detection (e.g. nephelometry) do not distinguish between active C3 and inactive breakdown products. C3-specific haemolytic assays can be used, but these require use of relatively unstable reagents. The current work represents a promising robust, enzyme- and antibody-free chemical method for detecting active thioester proteins in blood, plasma or serum.
Collapse
Affiliation(s)
- Lotta Holm
- Division of Physical Biochemistry, MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London NW7 1AA, UK
| | | | - Mark R. Edwards
- Centre for Anaesthesia, Critical Care and Pain Medicine, University College London Hospitals, University College London, London, UK
| | | | - Robert B. Sim
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, UK
| | - John Offer
- Division of Physical Biochemistry, MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London NW7 1AA, UK
- Corresponding author. Tel.: +44 20 88 16 20 82.
| |
Collapse
|
45
|
Substrate recognition by complement convertases revealed in the C5-cobra venom factor complex. EMBO J 2011; 30:606-16. [PMID: 21217642 DOI: 10.1038/emboj.2010.341] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2010] [Accepted: 11/26/2010] [Indexed: 11/08/2022] Open
Abstract
Complement acts as a danger-sensing system in the innate immune system, and its activation initiates a strong inflammatory response and cleavage of the proteins C3 and C5 by proteolytic enzymes, the convertases. These contain a non-catalytic substrate contacting subunit (C3b or C4b) in complex with a protease subunit (Bb or C2a). We determined the crystal structures of the C3b homologue cobra venom factor (CVF) in complex with C5, and in complex with C5 and the inhibitor SSL7 at 4.3 Å resolution. The structures reveal a parallel two-point attachment between C5 and CVF, where the presence of SSL7 only slightly affects the C5-CVF interface, explaining the IgA dependence for SSL7-mediated inhibition of C5 cleavage. CVF functions as a relatively rigid binding scaffold inducing a conformational change in C5, which positions its cleavage site in proximity to the serine protease Bb. A general model for substrate recognition by the convertases is presented based on the C5-CVF and C3b-Bb-SCIN structures. Prior knowledge concerning interactions between the endogenous convertases and their substrates is rationalized by this model.
Collapse
|
46
|
Li CJ, Li RW, Elsasser TH. Alpha-Tocopherol Modulates Transcriptional Activities that Affect Essential Biological Processes in Bovine Cells. GENE REGULATION AND SYSTEMS BIOLOGY 2010; 4:109-24. [PMID: 21157515 PMCID: PMC3001320 DOI: 10.4137/grsb.s6007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Using global expression profiling and pathway analysis on α-tocopherol-induced gene perturbation in bovine cells, this study has generated comprehensive information on the physiological functions of α-tocopherol. The data confirmed α-tocopherol is a potent regulator of gene expression and α-tocopherol possesses novel transcriptional activities that affect essential biological processes. The genes identified fall within a broad range of functional categories and provide the molecular basis for its distinctive effects. Enrichment analyses of gene regulatory networks indicate α-tocopherol alter the canonical pathway of lipid metabolism and transcription factors SREBP1 and SREBP2, (Sterol regulatory element binding proteins), which mediate the regulatory functions of lipid metabolism. Transcription factors HNF4-α (Hepatocyte nuclear factor 4), c-Myc, SP1 (Sp1 transcription factor), ESR1 (estrogen receptor 1, nuclear), and androgen receptor, along with several others, were centered as the hubs of transcription regulation networks. The data also provided direct evidence that α-tocopherol is involved in maintaining immuno-homeostasis through targeting the C3 (Complement Component 3) gene.
Collapse
Affiliation(s)
- Cong-Jun Li
- Bovine Functional Genomics Laboratory, Animal and Natural Resources Institute, ARS, USDA, 10300 Baltimore Ave, Beltsville, MD, 20705, USA
| | | | | |
Collapse
|
47
|
Self-association and domain rearrangements between complement C3 and C3u provide insight into the activation mechanism of C3. Biochem J 2010; 431:63-72. [PMID: 20666732 DOI: 10.1042/bj20100759] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Component C3 is the central protein of the complement system. During complement activation, the thioester group in C3 is slowly hydrolysed to form C3u, then the presence of C3u enables the rapid conversion of C3 into functionally active C3b. C3u shows functional similarities to C3b. To clarify this mechanism, the self-association properties and solution structures of C3 and C3u were determined using analytical ultracentrifugation and X-ray scattering. Sedimentation coefficients identified two different dimerization events in both proteins. A fast dimerization was observed in 50 mM NaCl but not in 137 mM NaCl. Low amounts of a slow dimerization was observed for C3u and C3 in both buffers. The X-ray radius of gyration RG values were unchanged for both C3 and C3u in 137 mM NaCl, but depend on concentration in 50 mM NaCl. The C3 crystal structure gave good X-ray fits for C3 in 137 mM NaCl. By randomization of the TED (thioester-containing domain)/CUB (for complement protein subcomponents C1r/C1s, urchin embryonic growth factor and bone morphogenetic protein 1) domains in the C3b crystal structure, X-ray fits showed that the TED/CUB domains in C3u are extended and differ from the more compact arrangement of C3b. This TED/CUB conformation is intermediate between those of C3 and C3b. The greater exposure of the TED domain in C3u (which possesses the hydrolysed reactive thioester) accounts for the greater self-association of C3u in low-salt conditions. This conformational variability of the TED/CUB domains would facilitate their interactions with a broad range of antigenic surfaces. The second dimerization of C3 and C3u may correspond to a dimer observed in one of the crystal structures of C3b.
Collapse
|
48
|
Baxter RHG, Steinert S, Chelliah Y, Volohonsky G, Levashina EA, Deisenhofer J. A heterodimeric complex of the LRR proteins LRIM1 and APL1C regulates complement-like immunity in Anopheles gambiae. Proc Natl Acad Sci U S A 2010; 107:16817-22. [PMID: 20826443 PMCID: PMC2947905 DOI: 10.1073/pnas.1010575107] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The leucine-rich repeat (LRR) proteins LRIM1 and APL1C control the function of the complement-like protein TEP1 in Anopheles mosquitoes. The molecular structure of LRIM1 and APL1C and the basis of their interaction with TEP1 represent a new type of innate immune complex. The LRIM1/APL1C complex specifically binds and solubilizes a cleaved form of TEP1 without an intact thioester bond. The LRIM1 and APL1C LRR domains have a large radius of curvature, glycosylated concave face, and a novel C-terminal capping motif. The LRIM1/APL1C complex is a heterodimer with a single intermolecular disulfide bond. The structure of the LRIM1/APL1C heterodimer reveals an interface between the two LRR domains and an extensive C-terminal coiled-coil domain. We propose that a cleaved form of TEP1 may act as a convertase for activation of other TEP1 molecules and that the LRIM1/APL1C heterodimer regulates formation of this TEP1 convertase.
Collapse
Affiliation(s)
- Richard H. G. Baxter
- Howard Hughes Medical Institute and Department of Biochemistry, University of Texas Southwestern Medical Center, 6001 Forest Park Road, Dallas, TX 75390-9050; and
| | - Stefanie Steinert
- Unité Propre de Recherche (UPR) 9022, Centre National de la Recherche Scientifique (CNRS), U 963, Inserm, Unité Mixte de Recherche (UMR) 9022, Université de Strasbourg, Institut de Biologie Moléculaire et Cellulaire, 15, Rue Rene Descartes, Strasbourg 67084 Cedex, France
| | - Yogarany Chelliah
- Howard Hughes Medical Institute and Department of Biochemistry, University of Texas Southwestern Medical Center, 6001 Forest Park Road, Dallas, TX 75390-9050; and
| | - Gloria Volohonsky
- Unité Propre de Recherche (UPR) 9022, Centre National de la Recherche Scientifique (CNRS), U 963, Inserm, Unité Mixte de Recherche (UMR) 9022, Université de Strasbourg, Institut de Biologie Moléculaire et Cellulaire, 15, Rue Rene Descartes, Strasbourg 67084 Cedex, France
| | - Elena A. Levashina
- Unité Propre de Recherche (UPR) 9022, Centre National de la Recherche Scientifique (CNRS), U 963, Inserm, Unité Mixte de Recherche (UMR) 9022, Université de Strasbourg, Institut de Biologie Moléculaire et Cellulaire, 15, Rue Rene Descartes, Strasbourg 67084 Cedex, France
| | - Johann Deisenhofer
- Howard Hughes Medical Institute and Department of Biochemistry, University of Texas Southwestern Medical Center, 6001 Forest Park Road, Dallas, TX 75390-9050; and
| |
Collapse
|
49
|
Sukovich DJ, Seffernick JL, Richman JE, Gralnick JA, Wackett LP. Widespread head-to-head hydrocarbon biosynthesis in bacteria and role of OleA. Appl Environ Microbiol 2010; 76:3850-62. [PMID: 20418421 PMCID: PMC2893475 DOI: 10.1128/aem.00436-10] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2010] [Accepted: 04/13/2010] [Indexed: 11/20/2022] Open
Abstract
Previous studies identified the oleABCD genes involved in head-to-head olefinic hydrocarbon biosynthesis. The present study more fully defined the OleABCD protein families within the thiolase, alpha/beta-hydrolase, AMP-dependent ligase/synthase, and short-chain dehydrogenase superfamilies, respectively. Only 0.1 to 1% of each superfamily represents likely Ole proteins. Sequence analysis based on structural alignments and gene context was used to identify highly likely ole genes. Selected microorganisms from the phyla Verucomicrobia, Planctomyces, Chloroflexi, Proteobacteria, and Actinobacteria were tested experimentally and shown to produce long-chain olefinic hydrocarbons. However, different species from the same genera sometimes lack the ole genes and fail to produce olefinic hydrocarbons. Overall, only 1.9% of 3,558 genomes analyzed showed clear evidence for containing ole genes. The type of olefins produced by different bacteria differed greatly with respect to the number of carbon-carbon double bonds. The greatest number of organisms surveyed biosynthesized a single long-chain olefin, 3,6,9,12,15,19,22,25,28-hentriacontanonaene, that contains nine double bonds. Xanthomonas campestris produced the greatest number of distinct olefin products, 15 compounds ranging in length from C(28) to C(31) and containing one to three double bonds. The type of long-chain product formed was shown to be dependent on the oleA gene in experiments with Shewanella oneidensis MR-1 ole gene deletion mutants containing native or heterologous oleA genes expressed in trans. A strain deleted in oleABCD and containing oleA in trans produced only ketones. Based on these observations, it was proposed that OleA catalyzes a nondecarboxylative thiolytic condensation of fatty acyl chains to generate a beta-ketoacyl intermediate that can decarboxylate spontaneously to generate ketones.
Collapse
Affiliation(s)
- David J. Sukovich
- Graduate Program in Microbiology, Immunology, and Cancer Biology, BioTechnology Institute, Department of Biochemistry, Molecular Biology and Biophysics, Department of Microbiology, University of Minnesota, St. Paul, Minnesota 55108
| | - Jennifer L. Seffernick
- Graduate Program in Microbiology, Immunology, and Cancer Biology, BioTechnology Institute, Department of Biochemistry, Molecular Biology and Biophysics, Department of Microbiology, University of Minnesota, St. Paul, Minnesota 55108
| | - Jack E. Richman
- Graduate Program in Microbiology, Immunology, and Cancer Biology, BioTechnology Institute, Department of Biochemistry, Molecular Biology and Biophysics, Department of Microbiology, University of Minnesota, St. Paul, Minnesota 55108
| | - Jeffrey A. Gralnick
- Graduate Program in Microbiology, Immunology, and Cancer Biology, BioTechnology Institute, Department of Biochemistry, Molecular Biology and Biophysics, Department of Microbiology, University of Minnesota, St. Paul, Minnesota 55108
| | - Lawrence P. Wackett
- Graduate Program in Microbiology, Immunology, and Cancer Biology, BioTechnology Institute, Department of Biochemistry, Molecular Biology and Biophysics, Department of Microbiology, University of Minnesota, St. Paul, Minnesota 55108
| |
Collapse
|
50
|
Structure, function, and insights into the biosynthesis of a head-to-head hydrocarbon in Shewanella oneidensis strain MR-1. Appl Environ Microbiol 2010; 76:3842-9. [PMID: 20418444 DOI: 10.1128/aem.00433-10] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A polyolefinic hydrocarbon was found in nonpolar extracts of Shewanella oneidensis MR-1 and identified as 3,6,9,12,15,19,22,25,28-hentriacontanonaene (compound I) by mass spectrometry, chemical modification, and nuclear magnetic resonance spectroscopy. Compound I was shown to be the product of a head-to-head fatty acid condensation biosynthetic pathway dependent on genes denoted as ole (for olefin biosynthesis). Four ole genes were present in S. oneidensis MR-1. Deletion of the entire oleABCD gene cluster led to the complete absence of nonpolar extractable products. Deletion of the oleC gene alone generated a strain that lacked compound I but produced a structurally analogous ketone. Complementation of the oleC gene eliminated formation of the ketone and restored the biosynthesis of compound I. A recombinant S. oneidensis strain containing oleA from Stenotrophomonas maltophilia strain R551-3 produced at least 17 related long-chain compounds in addition to compound I, 13 of which were identified as ketones. A potential role for OleA in head-to-head condensation was proposed. It was further proposed that long-chain polyunsaturated compounds aid in adapting cells to a rapid drop in temperature, based on three observations. In S. oneidensis wild-type cells, the cellular concentration of polyunsaturated compounds increased significantly with decreasing growth temperature. Second, the oleABCD deletion strain showed a significantly longer lag phase than the wild-type strain when shifted to a lower temperature. Lastly, compound I has been identified in a significant number of bacteria isolated from cold environments.
Collapse
|