Conformational switches modulate protein interactions in peptide antibiotic synthetases.
Protein dynamics plays an important role in protein function. Many functionally important motions occur on the microsecond and low millisecond time scale and can be characterized by nuclear magnetic resonance relaxation experiments. We describe the different states of a peptidyl carrier protein (PCP) that play a crucial role in its function as a peptide shuttle in the nonribosomal peptide synthetases of the tyrocidine A system. Both apo-PCP (without the bound 4'-phosphopantetheine cofactor) and holo-PCP exist in two different stable conformations. We show that one of the apo conformations and one of the holo conformations are identical, whereas the two remaining conformations are only detectable by nuclear magnetic resonance spectroscopy in either the apo or holo form. We further demonstrate that this conformational diversity is an essential prerequisite for the directed movement of the 4'-PP cofactor and its interaction with externally acting proteins such as thioesterases and 4'-PP transferase.
Koglin
Alexander
A
Institute of Biophysical Chemistry, Centre for Biomolecular Magnetic Resonance (BMRZ), J.W. Goethe University of Frankfurt, Marie-Curie-Strasse, D-60439 Frankfurt/Main, Germany.
Mofid
Mohammad R
MR
Löhr
Frank
F
Schäfer
Birgit
B
Rogov
Vladimir V
VV
Blum
Marc-Michael
MM
Mittag
Tanja
T
Marahiel
Mohamed A
MA
Bernhard
Frank
F
Dötsch
Volker
V
D001059:Apoproteins / Q000737:chemistry / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism; D001665:Binding Sites; D002352:Carrier Proteins / Q000737:chemistry* / Q000378:metabolism*; D018360:Crystallography, X-Ray; D064429:Fatty Acid Synthases / Q000378:metabolism; D020035:Holoenzymes / Q000737:chemistry / Q000378:metabolism; D008958:Models, Molecular; D019906:Nuclear Magnetic Resonance, Biomolecular; D010204:Pantetheine / Q000031:analogs & derivatives / Q000378:metabolism; D010453:Peptide Synthases / Q000737:chemistry* / Q000378:metabolism*; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D013869:Thiolester Hydrolases / Q000378:metabolism; D014166:Transferases / Q000378:metabolism
D001059:Apoproteins; D001426:Bacterial Proteins; D002352:Carrier Proteins; D020035:Holoenzymes; D010204:Pantetheine; D014166:Transferases; D064429:Fatty Acid Synthases; D013869:Thiolester Hydrolases; C022738:thioesterase II; D010453:Peptide Synthases; C035180:tyrocidine synthetase; C003129:4'-phosphopantetheine