Structure of the lipopeptide antibiotic tsushimycin.
Bunkoczi, G., Vertesy, L., Sheldrick, G.M.(2005) Acta Crystallogr D Biol Crystallogr 61: 1160-1164
- PubMed: 16041082 
- DOI: https://doi.org/10.1107/S0907444905017270
- Primary Citation of Related Structures:  
1W3M - PubMed Abstract: 
The amphomycin derivative tsushimycin has been crystallized and its structure determined at 1.0 A resolution. The asymmetric unit contains 12 molecules and with 1300 independent atoms this structure is one of the largest solved using ab initio direct methods. The antibiotic is comprised of a cyclodecapeptide core, an exocyclic amino acid and a fatty-acid residue. Its backbone adopts a saddle-like conformation that is stabilized by a Ca2+ ion bound within the peptide ring and accounts for the Ca2+-dependence of this antibiotic class. Additional Ca2+ ions link the antibiotic molecules to dimers that enclose an empty space resembling a binding cleft. The dimers possess a large hydrophobic surface capable of interacting with the bacterial cell membrane. The antibiotic daptomycin may exhibit a similar conformation, as the amino-acid sequence is conserved at positions involved in Ca2+ binding.
Organizational Affiliation: 
Lehrstuhl für Strukturchemie, Georg-August Universität, Tammannstrasse 4, 37077 Göttingen, Germany. [email protected]