Journal: Nat Commun / Year: 2020 Title: Bivalent antibody pliers inhibit β-tryptase by an allosteric mechanism dependent on the IgG hinge. Authors: Henry R Maun / Rajesh Vij / Benjamin T Walters / Ashley Morando / Janet K Jackman / Ping Wu / Alberto Estevez / Xiaocheng Chen / Yvonne Franke / Michael T Lipari / Mark S Dennis / Daniel ...Authors: Henry R Maun / Rajesh Vij / Benjamin T Walters / Ashley Morando / Janet K Jackman / Ping Wu / Alberto Estevez / Xiaocheng Chen / Yvonne Franke / Michael T Lipari / Mark S Dennis / Daniel Kirchhofer / Claudio Ciferri / Kelly M Loyet / Tangsheng Yi / Charles Eigenbrot / Robert A Lazarus / James T Koerber / Abstract: Human β-tryptase, a tetrameric trypsin-like serine protease, is an important mediator of allergic inflammatory responses in asthma. Antibodies generally inhibit proteases by blocking substrate ...Human β-tryptase, a tetrameric trypsin-like serine protease, is an important mediator of allergic inflammatory responses in asthma. Antibodies generally inhibit proteases by blocking substrate access by binding to active sites or exosites or by allosteric modulation. The bivalency of IgG antibodies can increase potency via avidity, but has never been described as essential for activity. Here we report an inhibitory anti-tryptase IgG antibody with a bivalency-driven mechanism of action. Using biochemical and structural data, we determine that four Fabs simultaneously occupy four exosites on the β-tryptase tetramer, inducing allosteric changes at the small interface. In the presence of heparin, the monovalent Fab shows essentially no inhibition, whereas the bivalent IgG fully inhibits β-tryptase activity in a hinge-dependent manner. Our results suggest a model where the bivalent IgG acts akin to molecular pliers, pulling the tetramer apart into inactive β-tryptase monomers, and may provide an alternative strategy for antibody engineering.
A: Tryptase alpha/beta-1 B: Tryptase alpha/beta-1 D: Tryptase alpha/beta-1 C: Tryptase alpha/beta-1 E: Fab E104.v1 heavy chain F: Fab E104.v1 light chain G: Fab E104.v1 heavy chain H: Fab E104.v1 heavy chain I: Fab E104.v1 light chain J: Fab E104.v1 heavy chain K: Fab E104.v1 light chain L: Fab E104.v1 light chain hetero molecules
Tryptasealpha/beta-1 / Tryptase-1 / Tryptase I / Tryptase alpha-1
Mass: 30549.043 Da / Num. of mol.: 4 Source method: isolated from a genetically manipulated source Source: (gene. exp.) Homo sapiens (human) / Gene: TPSAB1, TPS1, TPS2, TPSB1 / Production host: Baculovirus expression vector pFastBac1-HM / References: UniProt: Q15661, tryptase
-
Antibody , 2 types, 8 molecules EGHJFIKL
#2: Antibody
FabE104.v1heavychain
Mass: 24232.307 Da / Num. of mol.: 4 Source method: isolated from a genetically manipulated source Source: (gene. exp.) Homo sapiens (human) / Production host: Escherichia coli (E. coli)
#3: Antibody
FabE104.v1lightchain
Mass: 23601.156 Da / Num. of mol.: 4 Source method: isolated from a genetically manipulated source Source: (gene. exp.) Homo sapiens (human) / Production host: Escherichia coli (E. coli)
In the structure databanks used in Yorodumi, some data are registered as the other names, "COVID-19 virus" and "2019-nCoV". Here are the details of the virus and the list of structure data.
Jan 31, 2019. EMDB accession codes are about to change! (news from PDBe EMDB page)
EMDB accession codes are about to change! (news from PDBe EMDB page)
The allocation of 4 digits for EMDB accession codes will soon come to an end. Whilst these codes will remain in use, new EMDB accession codes will include an additional digit and will expand incrementally as the available range of codes is exhausted. The current 4-digit format prefixed with “EMD-” (i.e. EMD-XXXX) will advance to a 5-digit format (i.e. EMD-XXXXX), and so on. It is currently estimated that the 4-digit codes will be depleted around Spring 2019, at which point the 5-digit format will come into force.
The EM Navigator/Yorodumi systems omit the EMD- prefix.
Related info.:Q: What is EMD? / ID/Accession-code notation in Yorodumi/EM Navigator
Yorodumi is a browser for structure data from EMDB, PDB, SASBDB, etc.
This page is also the successor to EM Navigator detail page, and also detail information page/front-end page for Omokage search.
The word "yorodu" (or yorozu) is an old Japanese word meaning "ten thousand". "mi" (miru) is to see.
Related info.:EMDB / PDB / SASBDB / Comparison of 3 databanks / Yorodumi Search / Aug 31, 2016. New EM Navigator & Yorodumi / Yorodumi Papers / Jmol/JSmol / Function and homology information / Changes in new EM Navigator and Yorodumi