Complete Reconstitution and Deorphanization of the 3 MDa Nocardiosis-Associated Polyketide Synthase.
J Am Chem Soc
; 142(13): 5952-5957, 2020 04 01.
Article
em En
| MEDLINE
| ID: mdl-32182063
ABSTRACT
Several Nocardia strains associated with nocardiosis, a potentially life-threatening disease, house a nonamodular assembly line polyketide synthase (PKS) that presumably synthesizes an unknown polyketide. Here, we report the discovery and structure elucidation of the NOCAP (nocardiosis-associated polyketide) aglycone by first fully reconstituting the NOCAP synthase in vitro from purified protein components followed by heterologous expression in E. coli and spectroscopic analysis of the purified products. The NOCAP aglycone has an unprecedented structure comprised of a substituted resorcylaldehyde headgroup linked to a 15-carbon tail that harbors two conjugated all-trans trienes separated by a stereogenic hydroxyl group. This report is the first example of reconstituting a trans-acyltransferase assembly line PKS in vitro and of using these approaches to "deorphanize" a complete assembly line PKS identified via genomic sequencing. With the NOCAP aglycone in hand, the stage is set for understanding how this PKS and associated tailoring enzymes confer an advantage to their native hosts during human Nocardia infections.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Bactérias
/
Policetídeo Sintases
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Policetídeos
/
Nocardia
/
Nocardiose
Tipo de estudo:
Risk_factors_studies
Limite:
Humans
Idioma:
En
Ano de publicação:
2020
Tipo de documento:
Article