The crystal structure of samarosporin I at atomic resolution.
J Pept Sci
; 18(11): 678-84, 2012 Nov.
Article
en En
| MEDLINE
| ID: mdl-23019149
ABSTRACT
The atomic resolution structures of samarosporin I have been determined at 100 and 293 K. This is the first crystal structure of a natural 15-residue peptaibol. The amino acid sequence in samarosporin I is identical to emerimicin IV and stilbellin I. Samarosporin is a peptide antibiotic produced by the ascomycetous fungus Samarospora rostrup and belongs to peptaibol subfamily 2. The structures at both temperatures are very similar to each other adopting mainly a 310-helical and a minor fraction of α-helical conformation. The helices are significantly bent and packed in an antiparallel fashion in the centered monoclinic lattice leaving among them an approximately 10-Å channel extending along the crystallographic twofold axis. Only two ordered water molecules per peptide molecule were located in the channel. Comparisons have been carried out with crystal structures of subfamily 2 16-residue peptaibols antiamoebin and cephaibols. The repercussion of the structural analysis of samarosporin on membrane function is discussed.
Texto completo:
1
Colección:
01-internacional
Asunto principal:
Péptidos
/
Modelos Moleculares
Idioma:
En
Revista:
J Pept Sci
Asunto de la revista:
BIOQUIMICA
Año:
2012
Tipo del documento:
Article
País de afiliación:
Grecia