EMD-24863
CryoEM map of modular PKS holo-Lsd14 bound to antibody fragment 1B2, stalled at the condensation step, focused refinement of KS-KS'-ACP domains
EMD-24863
Single-particle3.2 Å
Deposition: 13/09/2021Map released: 27/07/2022
Last modified: 27/07/2022
Sample Organism:
Streptomyces lasalocidi
Sample: Dimeric holo-Lsd14 containing docking domains from DEBS module 3 (holo-Lsd14-DD*) bound to two copies each of Fab 1B2 light and heavy chains and NADP, treated with 2-Acetaminoethyl-thio-3-oxobutanoate
Deposition Authors: Bagde SR
,
Kim C-Y,
Fromme JC
Sample: Dimeric holo-Lsd14 containing docking domains from DEBS module 3 (holo-Lsd14-DD*) bound to two copies each of Fab 1B2 light and heavy chains and NADP, treated with 2-Acetaminoethyl-thio-3-oxobutanoate
Deposition Authors: Bagde SR
,
Kim C-Y,
Fromme JC
Modular polyketide synthase contains two reaction chambers that operate asynchronously.
Abstract:
Type I modular polyketide synthases are homodimeric multidomain assembly line enzymes that synthesize a variety of polyketide natural products by performing polyketide chain extension and β-keto group modification reactions. We determined the 2.4-angstrom-resolution x-ray crystal structure and the 3.1-angstrom-resolution cryo–electron microscopy structure of the Lsd14 polyketide synthase, stalled at the transacylation and condensation steps, respectively. These structures revealed how the constituent domains are positioned relative to each other, how they rearrange depending on the step in the reaction cycle, and the specific interactions formed between the domains. Like the evolutionarily related mammalian fatty acid synthase, Lsd14 contains two reaction chambers, but only one chamber in Lsd14 has the full complement of catalytic domains, indicating that only one chamber produces the polyketide product at any given time.
Type I modular polyketide synthases are homodimeric multidomain assembly line enzymes that synthesize a variety of polyketide natural products by performing polyketide chain extension and β-keto group modification reactions. We determined the 2.4-angstrom-resolution x-ray crystal structure and the 3.1-angstrom-resolution cryo–electron microscopy structure of the Lsd14 polyketide synthase, stalled at the transacylation and condensation steps, respectively. These structures revealed how the constituent domains are positioned relative to each other, how they rearrange depending on the step in the reaction cycle, and the specific interactions formed between the domains. Like the evolutionarily related mammalian fatty acid synthase, Lsd14 contains two reaction chambers, but only one chamber in Lsd14 has the full complement of catalytic domains, indicating that only one chamber produces the polyketide product at any given time.