Avian MRP126 Restricts Microbial Growth through Ca(II)-Dependent Zn(II) Sequestration
The calgranulins form a class of S100 proteins in higher vertebrates that innate-immune cells release in abundance at infection sites. These proteins function by binding transition metal ions to prevent microbial pathogens from obtaining those essential nutrients. Mammals express three distinct memb...
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| Format: | Article |
| Language: | English |
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American Chemical Society (ACS)
2020
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| Online Access: | https://hdl.handle.net/1721.1/128016 |
| _version_ | 1826196103559643136 |
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| author | Bozzi, Aaron Thomas Nolan, Elizabeth Marie |
| author2 | Massachusetts Institute of Technology. Department of Chemistry |
| author_facet | Massachusetts Institute of Technology. Department of Chemistry Bozzi, Aaron Thomas Nolan, Elizabeth Marie |
| author_sort | Bozzi, Aaron Thomas |
| collection | MIT |
| description | The calgranulins form a class of S100 proteins in higher vertebrates that innate-immune cells release in abundance at infection sites. These proteins function by binding transition metal ions to prevent microbial pathogens from obtaining those essential nutrients. Mammals express three distinct members of this family: S100A8 (calgranulin A), S100A9 (calgranulin B, which heterooligomerizes with S100A8 to form calprotectin), and S100A12 (calgranulin C), that exhibit Ca(II)-dependent transition metal binding properties. Human calprotectin effectively sequesters Mn(II), Fe(II), Ni(II), and Zn(II), whereas human S100A12 selectively sequesters Zn(II) over these other metal ions. Birds and reptiles express a single calgranulin homologue named MRP126, which we reasoned could have properties more similar to those of either calprotectin or S100A12. Here we present the purification and biophysical characterization of recombinant chicken MRP126 and, to the best of our knowledge, provide the first assessment of the metal binding and antimicrobial properties of an avian MRP126. We show that MRP126 is a homodimer that selectively sequesters Zn(II) and restricts the growth of certain microbes. MRP126 binds Zn(II) at two canonical His3Asp sites. The presence of excess Ca(II) increases the affinity of the His3Asp sites from the low-nanomolar to the low-picomolar range, thereby enhancing antimicrobial activity. Chicken MRP126 also binds additional Zn(II) equivalents with low-nanomolar affinity at two nonconserved dicysteine sites and with high-nanomolar affinity using a histidine-rich C-terminal tail that is a hallmark of this clade of calgranulins. Our results with chicken MRP126 suggest that Ca(II)-dependent Zn(II) sequestration was a role of the last common ancestor of calgranulin proteins, with mammalian calprotectin subsequently evolving a broader metal binding repertoire. |
| first_indexed | 2024-09-23T10:21:14Z |
| format | Article |
| id | mit-1721.1/128016 |
| institution | Massachusetts Institute of Technology |
| language | English |
| last_indexed | 2024-09-23T10:21:14Z |
| publishDate | 2020 |
| publisher | American Chemical Society (ACS) |
| record_format | dspace |
| spelling | mit-1721.1/1280162022-09-26T17:24:01Z Avian MRP126 Restricts Microbial Growth through Ca(II)-Dependent Zn(II) Sequestration Bozzi, Aaron Thomas Nolan, Elizabeth Marie Massachusetts Institute of Technology. Department of Chemistry The calgranulins form a class of S100 proteins in higher vertebrates that innate-immune cells release in abundance at infection sites. These proteins function by binding transition metal ions to prevent microbial pathogens from obtaining those essential nutrients. Mammals express three distinct members of this family: S100A8 (calgranulin A), S100A9 (calgranulin B, which heterooligomerizes with S100A8 to form calprotectin), and S100A12 (calgranulin C), that exhibit Ca(II)-dependent transition metal binding properties. Human calprotectin effectively sequesters Mn(II), Fe(II), Ni(II), and Zn(II), whereas human S100A12 selectively sequesters Zn(II) over these other metal ions. Birds and reptiles express a single calgranulin homologue named MRP126, which we reasoned could have properties more similar to those of either calprotectin or S100A12. Here we present the purification and biophysical characterization of recombinant chicken MRP126 and, to the best of our knowledge, provide the first assessment of the metal binding and antimicrobial properties of an avian MRP126. We show that MRP126 is a homodimer that selectively sequesters Zn(II) and restricts the growth of certain microbes. MRP126 binds Zn(II) at two canonical His3Asp sites. The presence of excess Ca(II) increases the affinity of the His3Asp sites from the low-nanomolar to the low-picomolar range, thereby enhancing antimicrobial activity. Chicken MRP126 also binds additional Zn(II) equivalents with low-nanomolar affinity at two nonconserved dicysteine sites and with high-nanomolar affinity using a histidine-rich C-terminal tail that is a hallmark of this clade of calgranulins. Our results with chicken MRP126 suggest that Ca(II)-dependent Zn(II) sequestration was a role of the last common ancestor of calgranulin proteins, with mammalian calprotectin subsequently evolving a broader metal binding repertoire. 2020-10-16T14:33:42Z 2020-10-16T14:33:42Z 2019-12 2019-12 2020-10-05T13:29:39Z Article http://purl.org/eprint/type/JournalArticle 0006-2960 1520-4995 https://hdl.handle.net/1721.1/128016 Bozzi, Aaron T. and Elizabeth M. Nolan. "Avian MRP126 Restricts Microbial Growth through Ca(II)-Dependent Zn(II) Sequestration." Biochemistry 59, 6 (December 2019): 802–817 © 2019 American Chemical Society en http://dx.doi.org/10.1021/acs.biochem.9b01012 Biochemistry Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf application/pdf American Chemical Society (ACS) Prof. Nolan via Ye Li |
| spellingShingle | Bozzi, Aaron Thomas Nolan, Elizabeth Marie Avian MRP126 Restricts Microbial Growth through Ca(II)-Dependent Zn(II) Sequestration |
| title | Avian MRP126 Restricts Microbial Growth through Ca(II)-Dependent Zn(II) Sequestration |
| title_full | Avian MRP126 Restricts Microbial Growth through Ca(II)-Dependent Zn(II) Sequestration |
| title_fullStr | Avian MRP126 Restricts Microbial Growth through Ca(II)-Dependent Zn(II) Sequestration |
| title_full_unstemmed | Avian MRP126 Restricts Microbial Growth through Ca(II)-Dependent Zn(II) Sequestration |
| title_short | Avian MRP126 Restricts Microbial Growth through Ca(II)-Dependent Zn(II) Sequestration |
| title_sort | avian mrp126 restricts microbial growth through ca ii dependent zn ii sequestration |
| url | https://hdl.handle.net/1721.1/128016 |
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