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Potok P, Zawada M, Potocki S. Determination of the role of specific amino acids in the binding of Zn(II), Ni(II), and Cu(II) to the active site of the M10 family metallopeptidase. J Inorg Biochem 2024; 253:112500. [PMID: 38301386 DOI: 10.1016/j.jinorgbio.2024.112500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 01/17/2024] [Accepted: 01/26/2024] [Indexed: 02/03/2024]
Abstract
Metallopeptidases are a group of metal-dependent enzymes that hydrolyze peptide bonds. These enzymes found in Streptococcus pneumoniae assist the pathogen in infecting the host by breaking down host tissues and extracellular matrix proteins. Considering metallopeptidases' significant role in bacterial virulence, inhibiting this enzyme represents a promising avenue for research. These enzymes are characterized by the presence of Zn(II) in the active site, proper coordination of which is essential for their catalytic function. This work aims to determine the significance of the specific amino acids in the metal binding domain of metallopeptidase from S. pneumoniae. For this purpose, we investigated the coordination chemistry of Zn(II), Ni(II), and Cu(II) ions with point-mutated peptide models of the metal-binding domain. Mutations were introduced at His-2 (L1) and Glu-1. Studies have shown that at pH 7.14 (pH of infected lungs by S. pneumoniae), point mutation on glutamic acid caused only minor effects on the binding of Zn(II) and Ni(II), while significantly improving Cu(II) binding. The stability of copper complexes is greater with the mutant Glu-1 → Gln-1 than with the original domain due to a hydrogen bonding network created by the Gln backbone with its side chain. Substituting histidine resulted in a significant reduction in metal binding for all metal ions, highlighting the crucial role of His-2 in metal coordination. Introduced mutations at neutral pH did not significantly affect the secondary structure of metal complexes. However, at alkaline pH, the peptides showed a higher percentage of antiparallel β-sheet structures upon the addition of Cu(II), Ni(II) and Zn(II).
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Affiliation(s)
- Paulina Potok
- Faculty of Chemistry, University of Wroclaw, 50-383 Wroclaw, Poland
| | - Martyna Zawada
- Faculty of Chemistry, University of Wroclaw, 50-383 Wroclaw, Poland
| | - Sławomir Potocki
- Faculty of Chemistry, University of Wroclaw, 50-383 Wroclaw, Poland.
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Cell Type-Specific Pherophorins of Volvox carteri Reveal Interplay of Both Cell Types in ECM Biosynthesis. Cells 2022; 12:cells12010134. [PMID: 36611928 PMCID: PMC9818292 DOI: 10.3390/cells12010134] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 12/14/2022] [Accepted: 12/27/2022] [Indexed: 12/31/2022] Open
Abstract
The spheroidal green algae Volvox carteri serves as a model system to investigate the formation of a complex, multifunctional extracellular matrix (ECM) in a relatively simple, multicellular organism with cell differentiation. The V. carteri ECM is mainly composed of hydroxyproline-rich glycoproteins (HRGPs) and there are diverse region-specific, anatomically distinct structures in the ECM. One large protein family with importance for ECM biosynthesis stands out: the pherophorins. The few pherophorins previously extracted from the ECM and characterized, were specifically expressed by somatic cells. However, the localization and function of most pherophorins is unknown. Here, we provide a phylogenetic analysis of 153 pherophorins of V. carteri and its unicellular relative Chlamydomonas reinhardtii. Our analysis of cell type-specific mRNA expression of pherophorins in V. carteri revealed that, contrary to previous assumptions, only about half (52%) of the 102 investigated pherophorin-related genes show stronger expression in somatic cells, whereas about one-third (34%) of the genes show significant higher expression in reproductive cells (gonidia). We fused two pherophorin genes that are expressed by different cell types to yfp, stably expressed them in Volvox and studied the tagged proteins by live-cell imaging. In contrast to earlier biochemical approaches, this genetic approach also allows the in vivo analysis of non-extractable, covalently cross-linked ECM proteins. We demonstrate that the soma-specific pherophorin SSG185 is localized in the outermost ECM structures of the spheroid, the boundary zone and at the flagellar hillocks. SSG185:YFP is detectable as early as 1.5 h after completion of embryogenesis. It is then present for the rest of the life cycle. The gonidia-specific pherophorin PhG is localized in the gonidial cellular zone 1 ("gonidial vesicle") suggesting its involvement in the protection of gonidia and developing embryos until hatching. Even if somatic cells produce the main portion of the ECM of the spheroids, ECM components produced by gonidia are also required to cooperatively assemble the total ECM. Our results provide insights into the evolution of the pherophorin protein family and convey a more detailed picture of Volvox ECM synthesis.
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Long Z. Computational analysis of the metal selectivity of matrix metalloproteinase 8. PLoS One 2020; 15:e0243321. [PMID: 33275641 PMCID: PMC7717551 DOI: 10.1371/journal.pone.0243321] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 11/18/2020] [Indexed: 11/18/2022] Open
Abstract
Matrix metalloproteinase (MMP) is a class of metalloenzyme that cleaves peptide bonds in extracellular matrices. Their functions are important in both health and disease of animals. Here using quantum mechanics simulations of the MMP8 protein, the coordination chemistry of different metal cofactors is examined. Structural comparisons reveal that Jhan-Teller effects induced by Cu(II) coordination distorts the wild-type MMP8 active site corresponding to a significant reduction in activity observed in previous experiments. In addition, further analysis suggests that a histidine to glutamine mutation at residue number 197 can potentially allow the MMP8 protein to utilize Cu(II) in reactions. Simulations also demonstrates the requirement of a conformational change in the ligand before enzymatic cleavage. The insights provided here will assist future protein engineering efforts utilizing the MMP8 protein.
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Affiliation(s)
- Zheng Long
- Department of Chemistry and Biochemistry, University of California San Diego, San Diego, California, United States of America
- * E-mail:
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From economy to luxury: Copper homeostasis in Chlamydomonas and other algae. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2020; 1867:118822. [PMID: 32800924 DOI: 10.1016/j.bbamcr.2020.118822] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 08/03/2020] [Accepted: 08/05/2020] [Indexed: 12/12/2022]
Abstract
Plastocyanin and cytochrome c6, abundant proteins in photosynthesis, are readouts for cellular copper status in Chlamydomonas and other algae. Their accumulation is controlled by a transcription factor copper response regulator (CRR1). The replacement of copper-containing plastocyanin with heme-containing cytochrome c6 spares copper and permits preferential copper (re)-allocation to cytochrome oxidase. Under copper-replete situations, the quota depends on abundance of various cuproproteins and is tightly regulated, except under zinc-deficiency where acidocalcisomes over-accumulate Cu(I). CRR1 has a transcriptional activation domain, a Zn-dependent DNA binding SBP-domain with a nuclear localization signal, and a C-terminal Cys-rich region that represses the zinc regulon. CRR1 activates >60 genes in Chlamydomonas through GTAC-containing CuREs; transcriptome differences are recapitulated in the proteome. The differentially-expressed genes encode assimilatory copper transporters of the CTR/SLC31 family including a novel soluble molecule, redox enzymes in the tetrapyrrole pathway that promote chlorophyll biosynthesis and photosystem 1 accumulation, and other oxygen-dependent enzymes, which may influence thylakoid membrane lipids, specifically polyunsaturated galactolipids and γ-tocopherol. CRR1 also down-regulates 2 proteins in Chlamydomonas: for plastocyanin, by activation of proteolysis, while for the di‑iron subunit of the cyclase in chlorophyll biosynthesis, through activation of an upstream promoter that generates a poorly-translated 5' extended transcript containing multiple short ORFs that inhibit translation. The functions of many CRR1-target genes are unknown, and the copper protein inventory in Chlamydomonas includes several whose functions are unexplored. The comprehensive picture of cuproproteins and copper homeostasis in this system is well-suited for reverse genetic analyses of these under-investigated components in copper biology.
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Rawlings ND. Twenty-five years of nomenclature and classification of proteolytic enzymes. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2019; 1868:140345. [PMID: 31838087 DOI: 10.1016/j.bbapap.2019.140345] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 12/09/2019] [Accepted: 12/11/2019] [Indexed: 10/25/2022]
Abstract
Proteolytic enzymes and their homologues have been classified into clans by comparing the tertiary structures of the peptidase domains, into families by comparing the protein sequences of the peptidase domains, and into protein-species by comparing various attributes including domain architecture, substrate preference, inhibitor interactions, subcellular location, and phylogeny. The results are compared with the earlier classification (Rawlings and Barrett, 1993 [1]). The numbers of sequences, protein-species, families, clans and even catalytic type have substantially increased during the intervening 26 years. The alternative classifications by catalytic type and/or activity are shown not to reflect evolutionary relationships.
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Affiliation(s)
- Neil D Rawlings
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire CB10 1SD, UK.
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Thompson KJ, Wessling-Resnick M. ZIP14 is degraded in response to manganese exposure. Biometals 2019; 32:829-843. [PMID: 31541377 PMCID: PMC7755095 DOI: 10.1007/s10534-019-00216-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 09/10/2019] [Indexed: 12/16/2022]
Abstract
Manganese (Mn) is an essential element necessary for proper development and brain function. Circulating Mn levels are regulated by hepatobiliary clearance to limit toxic levels and prevent tissue deposition. To characterize mechanisms involved in hepatocyte Mn uptake, polarized human HepaRG cells were used for this study. Western blot analysis and immunofluorescence microscopy showed the Mn transporter ZIP14 was expressed and localized to the basolateral surface of polarized HepaRG cells. HepaRG cells took up 54Mn in a time- and temperature-dependent manner but uptake was reduced after exposure to Mn. This loss in transport activity was associated with decreased ZIP14 protein levels in response to Mn exposure. Mn-induced degradation of ZIP14 was blocked by bafilomycin A1, which increased localization of the transporter in Lamp1-positive vesicles. Mn exposure also down-regulated the Golgi proteins TMEM165 and GPP130 while the ER stress marker BiP was induced. These results indicate that Mn exposure decreases ZIP14 protein levels to limit subsequent uptake of Mn as a cytoprotective response. Thus, high levels of Mn may compromise first-pass-hepatic clearance mechanisms.
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Affiliation(s)
- Khristy J Thompson
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, 665 Huntington Avenue, Boston, MA, 02115, USA.
| | - Marianne Wessling-Resnick
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, 665 Huntington Avenue, Boston, MA, 02115, USA
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Arolas JL, Goulas T, Cuppari A, Gomis-Rüth FX. Multiple Architectures and Mechanisms of Latency in Metallopeptidase Zymogens. Chem Rev 2018; 118:5581-5597. [PMID: 29775286 DOI: 10.1021/acs.chemrev.8b00030] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Metallopeptidases cleave polypeptides bound in the active-site cleft of catalytic domains through a general base/acid mechanism. This involves a solvent molecule bound to a catalytic zinc and general regulation of the mechanism through zymogen-based latency. Sixty reported structures from 11 metallopeptidase families reveal that prosegments, mostly N-terminal of the catalytic domain, block the cleft regardless of their size. Prosegments may be peptides (5-14 residues), which are only structured within the zymogens, or large moieties (<227 residues) of one or two folded domains. While some prosegments globally shield the catalytic domain through a few contacts, others specifically run across the cleft in the same or opposite direction as a substrate, making numerous interactions. Some prosegments block the zinc by replacing the solvent with particular side chains, while others use terminal α-amino or carboxylate groups. Overall, metallopeptidase zymogens employ disparate mechanisms that diverge even within families, which supports that latency is less conserved than catalysis.
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Affiliation(s)
- Joan L Arolas
- Proteolysis Laboratory, Structural Biology Unit ("María-de-Maeztu" Unit of Excellence) , Molecular Biology Institute of Barcelona, Consejo Superior de Investigaciones Científicas , Barcelona Science Park, c/Baldiri Reixac 15-21 , 08028 Barcelona , Catalonia , Spain
| | - Theodoros Goulas
- Proteolysis Laboratory, Structural Biology Unit ("María-de-Maeztu" Unit of Excellence) , Molecular Biology Institute of Barcelona, Consejo Superior de Investigaciones Científicas , Barcelona Science Park, c/Baldiri Reixac 15-21 , 08028 Barcelona , Catalonia , Spain
| | - Anna Cuppari
- Proteolysis Laboratory, Structural Biology Unit ("María-de-Maeztu" Unit of Excellence) , Molecular Biology Institute of Barcelona, Consejo Superior de Investigaciones Científicas , Barcelona Science Park, c/Baldiri Reixac 15-21 , 08028 Barcelona , Catalonia , Spain
| | - F Xavier Gomis-Rüth
- Proteolysis Laboratory, Structural Biology Unit ("María-de-Maeztu" Unit of Excellence) , Molecular Biology Institute of Barcelona, Consejo Superior de Investigaciones Científicas , Barcelona Science Park, c/Baldiri Reixac 15-21 , 08028 Barcelona , Catalonia , Spain
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8
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Aydemir TB, Cousins RJ. The Multiple Faces of the Metal Transporter ZIP14 (SLC39A14). J Nutr 2018; 148:174-184. [PMID: 29490098 PMCID: PMC6251594 DOI: 10.1093/jn/nxx041] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 11/07/2017] [Indexed: 12/14/2022] Open
Abstract
The SLC39A family of metal transporters was identified through homologies with the Zrt- and Irt-like (ZIP) proteins from yeast and plants. Of all the ZIP transporters, ZIP14 is arguably the most robustly characterized in terms of function at the integrative level. Mice with a global knockout of Zip14 are viable, thus providing the opportunity to conduct physiologic experiments. In mice, Zip14 expression is highly tissue specific, with the greatest abundance in the jejunum > liver > heart > kidney > white adipose tissue > skeletal muscle > spleen > pancreas. A unique feature of Zip14 is its upregulation by proinflammatory conditions, particularly increased interleukin 6 (IL-6) and nitric oxide. The transcription factors AP-1, ATF4, and ATF6α are involved in Zip14 regulation. ZIP14 does not appear to be zinc-regulated. The Zip14 knockout phenotype shows multiple sites of ZIP14 function, including the liver, adipose tissue, brain, pancreas, and bone. A prominent feature of the Zip14 ablation is a reduction in intestinal barrier function and onset of metabolic endotoxemia. Many aspects of the phenotype are accentuated with age and accompany increased circulating IL-6. Studies with 65Zn, 59Fe [nontransferrin-bound iron (NTBI)] and 54Mn show that ZIP14 transports these metals. At a steady state, the plasma concentrations of zinc, NTBI, and manganese are such that zinc ions are the major substrate available for ZIP14 at the cell surface. Upregulation of ZIP14 accounts for the hypozincemia and hepatic zinc accumulation associated with acute inflammation and sepsis and is required for liver regeneration and resistance to endoplasmic reticulum (ER) stress. Zip14 ablation in mice produces a defect in manganese excretion that leads to excess manganese accumulation in the brain that produces characteristics of Parkinsonism.
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Affiliation(s)
- Tolunay B Aydemir
- Food Science and Human Nutrition Department and Center for Nutritional
Sciences, College of Agricultural and Life Sciences, University of Florida, Gainesville,
FL,Address correspondence to TBA (e-mail: )
| | - Robert J Cousins
- Food Science and Human Nutrition Department and Center for Nutritional
Sciences, College of Agricultural and Life Sciences, University of Florida, Gainesville,
FL
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Klein B, Wibberg D, Hallmann A. Whole transcriptome RNA-Seq analysis reveals extensive cell type-specific compartmentalization in Volvox carteri. BMC Biol 2017; 15:111. [PMID: 29179763 PMCID: PMC5704591 DOI: 10.1186/s12915-017-0450-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 10/30/2017] [Indexed: 12/20/2022] Open
Abstract
Background One of evolution’s most important achievements is the development and radiation of multicellular organisms with different types of cells. Complex multicellularity has evolved several times in eukaryotes; yet, in most lineages, an investigation of its molecular background is considerably challenging since the transition occurred too far in the past and, in addition, these lineages evolved a large number of cell types. However, for volvocine green algae, such as Volvox carteri, multicellularity is a relatively recent innovation. Furthermore, V. carteri shows a complete division of labor between only two cell types – small, flagellated somatic cells and large, immotile reproductive cells. Thus, V. carteri provides a unique opportunity to study multicellularity and cellular differentiation at the molecular level. Results This study provides a whole transcriptome RNA-Seq analysis of separated cell types of the multicellular green alga V. carteri f. nagariensis to reveal cell type-specific components and functions. To this end, 246 million quality filtered reads were mapped to the genome and valid expression data were obtained for 93% of the 14,247 gene loci. In the subsequent search for protein domains with assigned molecular function, we identified 9435 previously classified domains in 44% of all gene loci. Furthermore, in 43% of all gene loci we identified 15,254 domains that are involved in biological processes. All identified domains were investigated regarding cell type-specific expression. Moreover, we provide further insight into the expression pattern of previously described gene families (e.g., pherophorin, extracellular matrix metalloprotease, and VARL families). Our results demonstrate an extensive compartmentalization of the transcriptome between cell types: More than half of all genes show a clear difference in expression between somatic and reproductive cells. Conclusions This study constitutes the first transcriptome-wide RNA-Seq analysis of separated cell types of V. carteri focusing on gene expression. The high degree of differential expression indicates a strong differentiation of cell types despite the fact that V. carteri diverged relatively recently from its unicellular relatives. Our expression dataset and the bioinformatic analyses provide the opportunity to further investigate and understand the mechanisms of cell type-specific expression and its transcriptional regulation. Electronic supplementary material The online version of this article (doi:10.1186/s12915-017-0450-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Benjamin Klein
- Department of Cellular and Developmental Biology of Plants, University of Bielefeld, Universitätsstr. 25, 33615, Bielefeld, Germany
| | - Daniel Wibberg
- Center for Biotechnology (CeBiTec), University of Bielefeld, Bielefeld, Germany
| | - Armin Hallmann
- Department of Cellular and Developmental Biology of Plants, University of Bielefeld, Universitätsstr. 25, 33615, Bielefeld, Germany.
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Contesini FJ, Melo RRD, Sato HH. An overview of Bacillus proteases: from production to application. Crit Rev Biotechnol 2017; 38:321-334. [DOI: 10.1080/07388551.2017.1354354] [Citation(s) in RCA: 101] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Fabiano Jares Contesini
- Laboratory of Food Biochemistry, Department of Food Science, College of Food Engineering, State University of Campinas (UNICAMP), Campinas, SP, Brazil
| | - Ricardo Rodrigues de Melo
- Laboratory of Food Biochemistry, Department of Food Science, College of Food Engineering, State University of Campinas (UNICAMP), Campinas, SP, Brazil
| | - Hélia Harumi Sato
- Laboratory of Food Biochemistry, Department of Food Science, College of Food Engineering, State University of Campinas (UNICAMP), Campinas, SP, Brazil
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Marino-Puertas L, Goulas T, Gomis-Rüth FX. Matrix metalloproteinases outside vertebrates. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2017; 1864:2026-2035. [PMID: 28392403 DOI: 10.1016/j.bbamcr.2017.04.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Revised: 03/31/2017] [Accepted: 04/04/2017] [Indexed: 02/07/2023]
Abstract
The matrix metalloproteinase (MMP) family belongs to the metzincin clan of zinc-dependent metallopeptidases. Due to their enormous implications in physiology and disease, MMPs have mainly been studied in vertebrates. They are engaged in extracellular protein processing and degradation, and present extensive paralogy, with 23 forms in humans. One characteristic of MMPs is a ~165-residue catalytic domain (CD), which has been structurally studied for 14 MMPs from human, mouse, rat, pig and the oral-microbiome bacterium Tannerella forsythia. These studies revealed close overall coincidence and characteristic structural features, which distinguish MMPs from other metzincins and give rise to a sequence pattern for their identification. Here, we reviewed the literature available on MMPs outside vertebrates and performed database searches for potential MMP CDs in invertebrates, plants, fungi, viruses, protists, archaea and bacteria. These and previous results revealed that MMPs are widely present in several copies in Eumetazoa and higher plants (Tracheophyta), but have just token presence in eukaryotic algae. A few dozen sequences were found in Ascomycota (within fungi) and in double-stranded DNA viruses infecting invertebrates (within viruses). In contrast, a few hundred sequences were found in archaea and >1000 in bacteria, with several copies for some species. Most of the archaeal and bacterial phyla containing potential MMPs are present in human oral and gut microbiomes. Overall, MMP-like sequences are present across all kingdoms of life, but their asymmetric distribution contradicts the vertical descent model from a eubacterial or archaeal ancestor. This article is part of a Special Issue entitled: Matrix Metalloproteinases edited by Rafael Fridman.
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Affiliation(s)
- Laura Marino-Puertas
- 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..
| | - 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..
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Buhmann MT, Schulze B, Förderer A, Schleheck D, Kroth PG. Bacteria may induce the secretion of mucin-like proteins by the diatom Phaeodactylum tricornutum. JOURNAL OF PHYCOLOGY 2016; 52:463-74. [PMID: 26993172 DOI: 10.1111/jpy.12409] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Accepted: 01/19/2016] [Indexed: 05/10/2023]
Abstract
Benthic diatoms live in photoautotrophic/heterotrophic biofilm communities embedded in a matrix of secreted extracellular polymeric substances. Closely associated bacteria influence their growth, aggregation, and secretion of exopolymers. We have studied a diatom/bacteria model community, in which a marine Roseobacter strain is able to grow with secreted diatom exopolymers as a sole source of carbon. The strain influences the aggregation of Phaeodactylum tricornutum by inducing a morphotypic transition from planktonic, fusiform cells to benthic, oval cells. Analysis of the extracellular soluble proteome of P. tricornutum in the presence and absence of bacteria revealed constitutively expressed newly identified proteins with mucin-like domains that appear to be typical for extracellular diatom proteins. In contrast to mucins, the proline-, serine-, threonine-rich (PST) domains in these proteins were also found in combination with protease-, glucosidase- and leucine-rich repeat-domains. Bioinformatic functional predictions indicate that several of these newly identified diatom-specific proteins may be involved in algal defense, intercellular signaling, and aggregation.
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Affiliation(s)
| | - Birgit Schulze
- Fachbereich Biologie, Universität Konstanz, 78457, Konstanz, Germany
| | | | - David Schleheck
- Fachbereich Biologie, Universität Konstanz, 78457, Konstanz, Germany
| | - Peter G Kroth
- Fachbereich Biologie, Universität Konstanz, 78457, Konstanz, Germany
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13
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Kianianmomeni A, Ong CS, Rätsch G, Hallmann A. Genome-wide analysis of alternative splicing in Volvox carteri. BMC Genomics 2014; 15:1117. [PMID: 25516378 PMCID: PMC4378016 DOI: 10.1186/1471-2164-15-1117] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 12/11/2014] [Indexed: 11/15/2022] Open
Abstract
Background Alternative splicing is an essential mechanism for increasing transcriptome and proteome diversity in eukaryotes. Particularly in multicellular eukaryotes, this mechanism is involved in the regulation of developmental and physiological processes like growth, differentiation and signal transduction. Results Here we report the genome-wide analysis of alternative splicing in the multicellular green alga Volvox carteri. The bioinformatic analysis of 132,038 expressed sequence tags (ESTs) identified 580 alternative splicing events in a total of 426 genes. The predominant type of alternative splicing in Volvox is intron retention (46.5%) followed by alternative 5′ (17.9%) and 3′ (21.9%) splice sites and exon skipping (9.5%). Our analysis shows that in Volvox at least ~2.9% of the intron-containing genes are subject to alternative splicing. Considering the total number of sequenced ESTs, the Volvox genome seems to provide more favorable conditions (e.g., regarding length and GC content of introns) for the occurrence of alternative splicing than the genome of its close unicellular relative Chlamydomonas. Moreover, many randomly chosen alternatively spliced genes of Volvox do not show alternative splicing in Chlamydomonas. Since the Volvox genome contains about the same number of protein-coding genes as the Chlamydomonas genome (~14,500 protein-coding genes), we assumed that alternative splicing may play a key role in generation of genomic diversity, which is required to evolve from a simple one-cell ancestor to a multicellular organism with differentiated cell types (Mol Biol Evol 31:1402-1413, 2014). To confirm the alternative splicing events identified by bioinformatic analysis, several genes with different types of alternatively splicing have been selected followed by experimental verification of the predicted splice variants by RT-PCR. Conclusions The results show that our approach for prediction of alternative splicing events in Volvox was accurate and reliable. Moreover, quantitative real-time RT-PCR appears to be useful in Volvox for analyses of relationships between the appearance of specific alternative splicing variants and different kinds of physiological, metabolic and developmental processes as well as responses to environmental changes. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-1117) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Arash Kianianmomeni
- Department of Cellular and Developmental Biology of Plants, University of Bielefeld, Universitätsstr, 25, D-33615 Bielefeld, Germany.
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Abstract
The green lineage of chlorophyte algae and streptophytes form a large and diverse clade with multiple independent transitions to produce multicellular and/or macroscopically complex organization. In this review, I focus on two of the best-studied multicellular groups of green algae: charophytes and volvocines. Charophyte algae are the closest relatives of land plants and encompass the transition from unicellularity to simple multicellularity. Many of the innovations present in land plants have their roots in the cell and developmental biology of charophyte algae. Volvocine algae evolved an independent route to multicellularity that is captured by a graded series of increasing cell-type specialization and developmental complexity. The study of volvocine algae has provided unprecedented insights into the innovations required to achieve multicellularity.
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Affiliation(s)
- James G Umen
- Donald Danforth Plant Science Center, St. Louis, Missouri 63132
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15
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Árus D, Nagy NV, Dancs Á, Jancsó A, Berkecz R, Gajda T. A minimalist chemical model of matrix metalloproteinases--can small peptides mimic the more rigid metal binding sites of proteins? J Inorg Biochem 2013; 126:61-9. [PMID: 23787141 DOI: 10.1016/j.jinorgbio.2013.05.015] [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: 02/21/2013] [Revised: 05/27/2013] [Accepted: 05/27/2013] [Indexed: 11/24/2022]
Abstract
In order to mimic the active center of matrix metalloproteinases (MMPs), we synthesized a pentadecapeptide (Ac-KAHEFGHSLGLDHSK-NH2) corresponding to the catalytic zinc(II) binding site of human MMP-13. The multi-domain structural organization of MMPs fundamentally determines their metal binding affinity, catalytic activity and selectivity. Our potentiometric, UV-visible, CD, EPR, NMR, mass spectrometric and kinetic studies are aimed to explore the usefulness of such flexible peptides to mimic the more rigid metal binding sites of proteins, to examine the intrinsic metal binding properties of this naked sequence, as well as to contribute to the development of a minimalist, peptide-based chemical model of MMPs, including the catalytic properties. Since the multiimidazole environment is also characteristic for copper(II), and recently copper(II) containing variants of MMPs have been identified, we also studied the copper(II) complexes of the above peptide. Around pH 6-7 the peptide, similarly to MMPs, offers a {3Nim} coordination binding site for both zinc(II) and copper(II). In the case of copper(II), the formation of amide coordinated species at higher pH abolished the analogy with the copper(II) containing MMP variant. On the other hand, the zinc(II)-peptide system mimics some basic features of the MMP active sites: the main species around pH7 (ZnH2L) possesses a {3Nim,H2O} coordination environment, the deprotonation of the zinc-bound water takes place near the physiological pH, it forms relatively stable ternary complexes with hydroxamic acids, and the species ZnH2L(OH) and ZnH2L(OH)2 have notable hydrolytic activity between pH7 and 9.
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Affiliation(s)
- Dávid Árus
- Bioinorganic Chemistry Research Group of the Hungarian Academy of Sciences, University of Szeged, Szeged, Hungary
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16
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Abstract
Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases belonging to the metzincin clan. MMPs have been characterized in detail in mammals, and they have been shown to play key roles in many physiological and pathological processes. Plant MMP-like proteases exist, but relatively few have been characterized. It has been speculated that plant MMPs are involved in remodeling of the plant extracellular matrix during growth, development and stress response. However, the precise functions and physiological substrates in higher plants remain to be determined. In this brief overview, we summarize the current knowledge of MMPs in higher plants and algae.
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Affiliation(s)
- Giada Marino
- Department of Chemistry and Umeå Plant Science Centre, Umeå University, 90187 Umeå, Sweden.
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17
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Hallmann A. VCRPs, small cysteine-rich proteins, might be involved in extracellular signaling in the green alga Volvox. PLANT SIGNALING & BEHAVIOR 2008; 3:124-127. [PMID: 19704730 PMCID: PMC2634000 DOI: 10.4161/psb.3.2.5036] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2007] [Accepted: 09/12/2007] [Indexed: 05/28/2023]
Abstract
The sex-inducer of the spherical green alga Volvox carteri is one of the most potent biological effector molecules known: it is released into the medium by sexual males and triggers the switch to the sexual cleavage program in the reproductive cells of vegetatively grown males and females even at concentrations as low as 10(-16) M. In an adult Volvox alga, all cells are embedded in an extensive extracellular matrix (ECM), which constitutes >99% of the volume of the spheroid. There exist no cytoplasmic connections between the cells in an adult alga, so any signal transduction between different cells or from the organism's environment to a reproductive cell must involve the ECM. Recently, a small cysteine-rich extracellular protein, VCRP, was identified in Volvox and shown to be quickly synthesized by somatic cells in response to the sex-inducer. Due to its characteristics, VCRP was speculated to be an extracellular second messenger from somatic cells to reproductive cells. Here a related protein, VCRP2, is presented, exhibiting a 56% amino acid sequence identity with VCRP. Two possible scenarios for signal transduction from the sex-inducer to the reproductive cell are discussed.
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Affiliation(s)
- Armin Hallmann
- Department of Cellular and Developmental Biology of Plants; University of Bielefeld; Bielefeld, Germany
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Rawlings ND, Morton FR. The MEROPS batch BLAST: a tool to detect peptidases and their non-peptidase homologues in a genome. Biochimie 2007; 90:243-59. [PMID: 17980477 DOI: 10.1016/j.biochi.2007.09.014] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2007] [Accepted: 09/21/2007] [Indexed: 11/29/2022]
Abstract
Many of the 181 families of peptidases contain homologues that are known to have functions other than peptide bond hydrolysis. Distinguishing an active peptidase from a homologue that is not a peptidase requires specialist knowledge of the important active site residues, because replacement or lack of one of these catalytic residues is an important clue that the homologue in question is unlikely to hydrolyse peptide bonds. Now that the rate at which proteins are characterized is outstripped by the rate that genome sequences are determined, many genes are being incorrectly annotated because only sequence similarity is taken into consideration. We present a tool called the MEROPS batch BLAST which not only performs a comparison against the MEROPS sequence collection, but also does a pair-wise alignment with the closest homologue detected and calculates the position of the active site residues. A non-peptidase homologue can be distinguished by the absence or unacceptable replacement of any of these residues. An analysis of peptidase homologues in the genome of the bacterium Erythrobacter litoralis is presented as an example.
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Affiliation(s)
- Neil D Rawlings
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridgeshire CB10 1SA, UK.
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Merchant SS, Allen MD, Kropat J, Moseley JL, Long JC, Tottey S, Terauchi AM. Between a rock and a hard place: trace element nutrition in Chlamydomonas. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2006; 1763:578-94. [PMID: 16766055 DOI: 10.1016/j.bbamcr.2006.04.007] [Citation(s) in RCA: 154] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2006] [Revised: 04/06/2006] [Accepted: 04/06/2006] [Indexed: 11/23/2022]
Abstract
Photosynthetic organisms are among the earliest life forms on earth and their biochemistry is strictly dependent on a wide range of inorganic nutrients owing to the use of metal cofactor-dependent enzymes in photosynthesis, respiration, inorganic nitrogen and sulfur assimilation. Chlamydomonas reinhardtii is a photosynthetic eukaryotic model organism for the study of trace metal homeostasis. Chlamydomonas spp. are widely distributed and can be found in soil, glaciers, acid mines and sewage ponds, suggesting that the genus has significant capacity for acclimation to micronutrient availability. Analysis of the draft genome indicates that metal homeostasis mechanisms in Chlamydomonas represent a blend of mechanisms operating in animals, plants and microbes. A combination of classical genetics, differential expression and genomic analysis has led to the identification of homologues of components known to operate in fungi and animals (e.g., Fox1, Ftr1, Fre1, Fer1, Ctr1/2) as well as novel molecules involved in copper and iron nutrition (Crr1, Fea1/2). Besides activating iron assimilation pathways, iron-deficient Chlamydomonas cells re-adjust metabolism by reducing light delivery to photosystem I (to avoid photo-oxidative damage resulting from compromised FeS clusters) and by modifying the ferredoxin profile (perhaps to accommodate preferential allocation of reducing equivalents). Up-regulation of a MnSOD isoform may compensate for loss of FeSOD. Ferritin could function to buffer the iron released from programmed degradation of iron-containing enzymes in the chloroplast. Some metabolic adjustments are made in anticipation of deficiency while others occur only with sustained or severe deficiency. Copper-deficient Chlamydomonas cells induce a copper assimilation pathway consisting of a cell surface reductase and a Cu(+) transporter (presumed CTR homologue). There are metabolic adaptations in addition: the synthesis of "back-up" enzymes for plastocyanin in photosynthesis and the ferroxidase in iron assimilation plus activation of alternative oxidase to handle the electron "overflow" resulting from reduced cytochrome oxidase function. Oxygen-dependent enzymes in the tetrapyrrole pathway (coproporphyrinogen oxidase and aerobic oxidative cyclase) are also increased in expression and activity by as much as 10-fold but the connection between copper nutrition and tetrapyrroles is not understood. The copper-deficiency responses are mediated by copper response elements that are defined by a GTAC core sequence and a novel metalloregulator, Crr1, which uses a zinc-dependent SBP domain to bind to the CuRE. The Chlamydomonas model is ideal for future investigation of nutritional manganese deficiency and selenoenzyme function. It is also suited for studies of trace nutrient interactions, nutrition-dependent metabolic changes, the relationship between photo-oxidative stress and metal homeostasis, and the important questions of differential allocation of limiting metal nutrients (e.g., to respiration vs. photosynthesis).
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Affiliation(s)
- Sabeeha S Merchant
- Department of Chemistry and Biochemistry, Box 951569, University of California-Los Angeles, Los Angeles, CA 90095-1569, USA.
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Aono N, Inoue T, Shiraishi H. Genes specifically expressed in sexually differentiated female spheroids of Volvox carteri. J Biochem 2006; 138:375-82. [PMID: 16272131 DOI: 10.1093/jb/mvi139] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Volvox carteri is a multicellular green alga with only two cell types, somatic cells and reproductive cells. Phylogenetic analysis suggests that this organism has evolved from a Chlamydomonas-like unicellular ancestor along with multicellularity, cellular differentiation, and a change in the mode of sexual reproduction from isogamy to oogamy. To examine the mechanism of sexual differentiation and the evolution of oogamy, we isolated 6 different cDNA sequences specifically expressed in sexually differentiated female spheroids. The genes for the cDNAs were designated SEF1 to SEF6. The time course of accumulation of each mRNA was shown to be distinct. The expression of some of these genes was not significantly affected when the sexual inducer was removed after the induction of sexual development. Sequence analysis indicates that SEF5 and SEF6 encode pherophorin-related proteins. Of these, SEF5 has the unique structural feature of a polyproline stretch in the C-terminal domain in addition to the one found in the central region.
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Affiliation(s)
- Naoki Aono
- Graduate School of Science and Graduate School of Biostudies, Kyoto University, Kitashirakawa Oiwake-cho, Kyoto 606-8502, Japan
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21
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Hallmann A. The pherophorins: common, versatile building blocks in the evolution of extracellular matrix architecture in Volvocales. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2006; 45:292-307. [PMID: 16367971 DOI: 10.1111/j.1365-313x.2005.02627.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Green algae of the order Volvocales provide an unrivalled opportunity for exploring the transition from unicellularity to multicellularity. They range from unicells, like Chlamydomonas, through homocytic colonial forms with increasing cooperation of individual cells, like Gonium or Pandorina, to heterocytic multicellular forms with different cell types and a complete division of labour, like Volvox. A fundamental requirement for the evolution of multicellularity is the development of a complex, multifunctional extracellular matrix (ECM). The ECM has many functions, which can change under developmental control or as a result of environmental factors. Here molecular data from 15 novel proteins are presented. These proteins have been identified in Chlamydomonas reinhardtii, Gonium pectorale, Pandorina morum and Volvox carteri, and all belong to a single protein family, the pherophorins. Pherophorin-V1 is shown to be a glycoprotein localized to the 'cellular zone' of the V. carteri ECM. Pherophorin-V1 and -V2 mRNAs are strongly induced not only by the sex inducer, which triggers sexual development at extremely low concentrations, but also by mechanical wounding. Like the extensins of higher plants, which are also developmentally controlled or sometimes inducible by wounding, the pherophorins contain a (hydroxy-)proline-rich (HR) rod-like domain and are abundant within the extracellular compartment. In contrast to most extensins, pherophorins have additional globular A and B domains on both ends of the HR domains. Therefore pherophorins most closely resemble a particular class of higher plant extensin, the solanaceous lectins (e.g. potato lectin), suggesting multivalent carbohydrate-binding functions are present within the A and B domains and are responsible for cross-linking. Our results suggest that pherophorins are used as the building blocks for the extracellular scaffold throughout the Volvocales, with the characteristic mesh sizes in different ECM structures being a result of the highly diverse extensions of the HR domains. Pherophorins have therefore been a versatile element during the evolution of ECM architecture in these green algae.
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Affiliation(s)
- Armin Hallmann
- Department of Cellular and Developmental Biology of Plants, University of Bielefeld, Universitätsstr. 25, D-33615 Bielefeld, Germany.
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The metal-binding motif of dipeptidyl peptidase III directly influences the enzyme activity in the copper derivative of dipeptidyl peptidase III. Arch Biochem Biophys 2004; 431:1-8. [DOI: 10.1016/j.abb.2004.07.033] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2004] [Revised: 07/29/2004] [Indexed: 11/16/2022]
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Hua DH, Tamura M, Egi M, Werbovetz K, Delfín D, Salem M, Chiang PK. Antiprotozoal activities of symmetrical bishydroxamic acids. Bioorg Med Chem 2003; 11:4357-61. [PMID: 13129572 DOI: 10.1016/s0968-0896(03)00522-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Symmetrical bishydroxamic acids along with their sodium salts containing an alkyl spacer between two aromatic rings were synthesized, and their antiparasitic activities were evaluated. Bishydroxamic acids were conveniently prepared from the alkylation of methyl 4-hydroxybenzoate with various dihalo-alkane, -alkene, and -ether followed by reaction with hydroxylamine. Surprisingly, the bishydroxamic acids and their sodium salts possess strong inhibitory activities against Plasmodium falciparum parasites with IC50 values in the range of 0.26-3.2 microM. Bishydroxamic acid 3 and its sodium salt 12 also inhibit the growth of Leishmania donovani, albeit at higher concentrations. The corresponding biscarboxylic acids and bismethyl esters are inactive. Presumably, the ability of bishydroxamic acids to complex with metallic iron in hemoglobin may be responsible for antimalarial activity of these compounds.
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Affiliation(s)
- Duy H Hua
- Department of Chemistry, Kansas State University, Manhattan, KS 66506, USA.
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Taylor KM, Nicholson RI. The LZT proteins; the LIV-1 subfamily of zinc transporters. BIOCHIMICA ET BIOPHYSICA ACTA 2003; 1611:16-30. [PMID: 12659941 DOI: 10.1016/s0005-2736(03)00048-8] [Citation(s) in RCA: 193] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Zinc is an essential ion for cells with a vital role to play in controlling the cellular processes of the cell, such as growth, development and differentiation. Specialist proteins called zinc transporters control the level of intracellular zinc in cells. In mammals, the ZIP family of zinc transporters has a pivotal role in maintaining the correct level of intracellular zinc by their ability to transport zinc into cells from outside, although they may also transport metal ions other than zinc. There are now recognised to be four subfamilies of the ZIP transporters, including the recently discovered LIV-1 subfamily which has similarity to the oestrogen-regulated gene LIV-1, previously implicated in metastatic breast cancer. We call this new subfamily LZT, for LIV-1 subfamily of ZIP zinc Transporters. Here we document current knowledge of this previously uncharacterised group of proteins, which includes the KE4 proteins. LZT proteins are similar to ZIP transporters in secondary structure and ability to transport metal ions across the plasma membrane or intracellular membranes. However, LZT proteins have a unique motif (HEXPHEXGD) with conserved proline and glutamic acid residues, unprecedented in other zinc transporters. The localisation of LZT proteins to lamellipodiae mirrors cellular location of the membrane-type matrix metalloproteases. These differences to other zinc transporters may be consistent with an alternative role for LZT proteins in cells, particularly in diseases such as cancer.
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Affiliation(s)
- Kathryn M Taylor
- Tenovus Centre for Cancer Research, Welsh School of Pharmacy, Cardiff University, Redwood Building, King Edward VIIth Avenue, Cardiff CF10 3XF, UK.
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Hallmann A. Extracellular matrix and sex-inducing pheromone in Volvox. INTERNATIONAL REVIEW OF CYTOLOGY 2003; 227:131-82. [PMID: 14518551 DOI: 10.1016/s0074-7696(03)01009-x] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
During evolution of multicellularity it was imperative to create a complex, multifunctional extracellular matrix (ECM) out of the simple cell wall of a unicellular ancestor. The green alga Volvox represents one of the simplest multicellular organisms, but even so, it already has a highly developed ECM. This ECM is mainly composed of an assortment of glycoproteins, many of which are hydroxyproline rich and extensively sulfated. Several ECM proteins are cross-linked and might have only structural functions. However, the ECM does not represent a static but rather a dynamic and multifunctional interface between a cell and its neighboring cells or its environment. It not only provides protection and structural support for the shape of each cell and the organism as a whole, but also plays a broad range of biological roles in growth, development, reproduction, and responses to environmental stress or wounding. The variety of functions of the ECM requires many glycoproteins to do the work. To attain a high flexibility and adaptability, almost all ECM glycoproteins from Volvox consist of modules, defined as functional subunits that form modular mosaic proteins with an outstanding combinatorial potential. The ECM's functions are not only extensive but also change under developmental control or by environmental incidents. The changing scope of duties necessitates a permanent ECM turnover and remodeling. In Volvox carteri one particularly challenging trigger of such ECM modifications is a sex-inducing pheromone, which is one of the most potent biological effector molecules known: the glycoprotein pheromone is fully effective for inducing sexual development in males and females at concentrations as low as 10(-16) M. The earliest detectable response to the pheromone is the synthesis of ECM glycoproteins.
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Affiliation(s)
- Armin Hallmann
- Department of Cellular and Developmental Biology of Plants, University of Bielefeld, D-33615 Bielefeld, Germany
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Purton S, Pazour GJ. Meeting report: Tenth International Conference on the Cell and Molecular Biology of Chlamydomonas. Protist 2002; 153:325-36. [PMID: 12627862 DOI: 10.1078/14344610260450055] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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