The crystal structure of the 14-residue peptaibol trichovirin at atomic resolution

Authors: R. Gessmann (IMBB-FORTH, Greece) , D. A. Axford (Diamond Light Source) , R. L. Owen (Diamond Light Source) , H. Brueckner (University of Giessen, Germany) , K. Petratos (IMBB-FORTH, Greece)
Co-authored by industrial partner: No

Type: Conference Paper
Conference: EPS32 Athens, Greece
Peer Reviewed: No

State: Published (Approved)
Published: September 2012

Abstract: The 14-residue peptaibol antibiotic trichovirin I-4A (TV) of the linear, covalent structure Ac-Aib-Asn-Leu-Aib Pro-Ala-Val-Aib-Pro-Aib-Leu-Aib-Pro-Leuol (Ac, acetyl; Aib, α-aminoisobutyric acid; Leuol, L-leucinol) has been synthesized and very thin (~25 μm) hair-like crystals were obtained from a methanolacetonitrile- water mixture. Diffraction data were collected at 100 K at the Diamond Light Source England, using the microfocus beamline2 I24 and a X-ray beam focused to a size of 10 μm full-width-half-maximum. Two independent molecules (A) and (B) were located in the crystal’s asymmetric unit3. Both chains assume 4 complete turns of a curved 310 right-handed helical conformation stabilized by intramolecular hydrogen bonds. Up to now TV represents the longest right-handed 310-helix of a natural peptaibol sequence complementing those of synthetic, protected homooligo-Aib peptides. Based on the structure in polar environment a transition from 310-helical to an α-helical conformation at the water/lipid interface in bilayer membranes is hypothesized.

Subject Areas: Biology and Bio-materials

Instruments: I24-Microfocus Macromolecular Crystallography