1ZXF

Solution structure of a self-sacrificing resistance protein, CalC from Micromonospora echinospora


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structural insight into the self-sacrifice mechanism of enediyne resistance.

Singh, S.Hager, M.H.Zhang, C.Griffith, B.R.Lee, M.S.Hallenga, K.Markley, J.L.Thorson, J.S.

(2006) Acs Chem.Biol. 1: 451-460

  • DOI: 10.1021/cb6002898
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • The recent discovery of the first "self-sacrifice" mechanism for bacterial resistance to the enediyne antitumor antibiotics, where enediyne-induced proteolysis of the resistance protein CalC inactivates both the highly reactive metabolite and the res ...

    The recent discovery of the first "self-sacrifice" mechanism for bacterial resistance to the enediyne antitumor antibiotics, where enediyne-induced proteolysis of the resistance protein CalC inactivates both the highly reactive metabolite and the resistance protein, revealed yet another ingenious bacterial mechanism for controlling reactive metabolites. As reported herein, the first 3D structures of CalC and CalC in complex with calicheamicin (CLM) divulge CalC to be a member of the steroidogenic acute regulatory protein (StAR)-related transfer (START) domain superfamily. In contrast to previous studies of proteins known to bind DNA-damaging natural products ( e.g ., bleomycins, mitomycins, and nine-membered chromoprotein enediynes), this is the first demonstrated involvement of a START domain fold. Consistent with the CalC self-sacrifice mechanism, CLM in complex with CalC is positioned for direct hydrogen abstraction from Gly113 to initiate the oxidative proteolysis-based resistance mechanism. These structural studies also illuminate, for the first time, a small DNA-binding region within CalC that may serve to localize CalC to the enediyne target (DNA). Given the role of START domains in nuclear/cytosolic transport and translocation, this structural study also may implicate START domains as post-endocytotic intracellular chaperones for enediyne-based therapeutics such as MyloTarg.


    Related Citations: 
    • The calicheamicin gene cluster and its iterative type I enediyne PKS.
      Ahlert, J.,Shepard, E.,Lomovskaya, N.,Zazopoulos, E.,Staffa, A.,Bachmann, B.O.,Huang, K.,Fonstein, L.,Czisny, A.,Whitwam, R.E.,Farnet, C.M.,Thorson, J.S.
      (2002) Science 297: 1173
    • Resistance to enediyne antitumor antibiotics by CalC self-sacrifice.
      Biggins, J.B.,Onwueme, K.C.,Thorson, J.S.
      (2003) Science 301: 1537


    Organizational Affiliation

    Center for Eukaryotic Structural Genomics, Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706-1544, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
CalC
A
155Micromonospora echinosporaMutation(s): 0 
Gene Names: calC
Find proteins for Q8KNF0 (Micromonospora echinospora)
Go to UniProtKB:  Q8KNF0
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 
  • Olderado: 1ZXF Olderado

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2005-12-13
    Type: Initial release
  • Version 1.1: 2008-04-30
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance