5Z6E

Crystal structure of a beta gamma-crystallin domain of Abundant Perithecial Protein (APP) from Neurospora crassa in the Ca2+-bound form

Summary for 5Z6E

• Entry DOI: 10.2210/pdb5z6e/pdb
• Descriptor: DUF1881 domain-containing protein, CALCIUM ION, POTASSIUM ION, ... (4 entities in total)
• Functional Keywords: beta gamma-crystallin domain, abundant perithecial protein, calcium-binding protein, metal binding protein
• Biological source: Neurospora crassa (strain ATCC 24698 / 74-OR23-1A / CBS 708.71 / DSM 1257 / FGSC 987)
• Total number of polymer chains: 1
• Total formula weight: 11235.44

Authors

Srivastava, S.S.,Sankaranarayanan, R. (deposition date: 2018-01-22, release date: 2019-01-23, Last modification date: 2023-11-22)

Primary citation

Swaroop Srivastava, S.,Raman, R.,Kiran, U.,Garg, R.,Chadalawada, S.,Pawar, A.D.,Sankaranarayanan, R.,Sharma, Y.
Interface interactions between beta gamma-crystallin domain and Ig-like domain render Ca2+-binding site inoperative in abundant perithecial protein of Neurospora crassa.
Mol.Microbiol., 110:955-972, 2018

PubMed Abstract: We describe a set of proteins in which a βγ-crystallin domain pairs with an Ig-like domain, and which are confined to microbes, like bacteria, slime molds and fungi. DdCAD-1 (Ca -dependent cell adhesion molecule-1) and abundant perithecial protein (APP) represent this class of molecules. Using the crystal structure of APP-NTD (N-terminal domain of APP), we describe its mode of Ca binding and provide a generalized theme for correct identification of the Ca -binding site within this class of molecules. As a common feature, one of the two Ca -binding sites is non-functional in the βγ-crystallin domains of these proteins. While APP-NTD binds Ca with a micromolar affinity which is comparable to DdCAD-1, APP surprisingly does not bind Ca . Crystal structures of APP and Ca -bound APP-NTD reveal that the interface interactions in APP render its Ca -binding site inoperative. Thus, heterodomain association provides a novel mode of Ca -binding regulation in APP. Breaking the interface interactions (mutating Asp30Ala, Leu132Ala and Ile135Ala) or separation from the Ig-like domain removes the constraints upon the required conformational transition and enables the βγ-crystallin domain to bind Ca . In mechanistic detail, our work demonstrates an interdomain interface adapted to distinct functional niches in APP and its homolog DdCAD-1.

PubMed: 30216631
DOI: 10.1111/mmi.14130

Experimental method

X-RAY DIFFRACTION (1.864 Å)