Protein Domain : Pesticidal crystal protein Cry, domain V IPR041587

Type	Domain
Description	This entry represents a domain is found in the protoxin portion of insecticidal proteins (parasporins, or Cry proteins) such as Cry1Ac from Bacillus thuringiensis (Bt). These proteins contain a proteolytically labile protoxin segment (in the C-terminal region) and a three-domain toxic core at the N terminus (domains I-III). This entry describes domain V, one of the four protoxin domains (domains IV-VII). Domains V and VII are β-rolls (similar to domain II or III) that closely resemble carbohydrate-binding modules found in sugar hydrolases. However, it is unclear which particular carbohydrates (if any) may serve as their ligands because residues on the putative sugar-binding interfaces are conserved neither in sequence nor in local structure. Structural analysis of Bt Cry1Ac indicates that there are putative disulfide crosslinks at the dimer interface mediated by cysteines within region 783-823 of this domain. Together with other cysteines, these create a three-dimensional network of cross-links across the crystal which may play a role in stabilizing mature Bt Cry1Ac [ ].
Short Name	Cry_V