Jesús H. González Cortés

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The soluble, diffusible red-brown pigment produced by a Saccharopolyspora erythraea "red variant" has been shown to contain glycosylated and polymerized derivatives of 2,5,7-trihydroxy-1,4-naphthoquinone (flaviolin). Flaviolin is a spontaneous oxidation product of 1,3,6,8-tetrahydroxynaphthalene (THN), which is biosynthesized in bacteria by a chalcone(More)
The gene cluster (ery) responsible for production of the macrolide antibiotic erythromycin by Saccharopolyspora erythraea is also known to contain ermE, the gene conferring resistance to the antibiotic. The nucleotide sequence has been determined of a 4.5 kb portion of the biosynthetic gene cluster, from a region lying between 3.7 kb and 8.2 kb 3′ of ermE.(More)
The production of erythromycin A by Saccharopolysporaerythraea requires the synthesis of dTDP-D-desosamine and dTDP-L-mycarose, which serve as substrates for the transfer of the two sugar residues onto the macrolactone ring. The enzymatic activities involved in this process are largely encoded within the ery gene cluster, by two sets of genes flanking the(More)
Sequence comparisons of multiple acyltransferase (AT) domains from modular polyketide synthases (PKSs) have highlighted a correlation between a short sequence motif and the nature of the extender unit selected. When this motif was specifically altered in the bimodular model PKS DEBS1-TE of Saccharopolyspora erythraea, the products included triketide(More)
The gene cluster (ery) governing the biosynthesis of the macrolide antibiotic erythromycin A by Saccharopolyspora erythraea contains, in addition to the eryA genes encoding the polyketide synthase, two regions containing genes for later steps in the pathway. The region 5′ of eryA, and lying between eryA and the gene eryK, which is known to encode the C-12(More)
The genome of the erythromycin-producing bacterium Saccharopolyspora erythraea contains many orphan secondary metabolite gene clusters including two (nrps3 and nrps5) predicted to govern biosynthesis of nonribosomal peptide-based siderophores. We report here the production by S. erythraea, even under iron-sufficient conditions, of a 2,5-diketopiperazine(More)
Mersacidin is a tetracyclic lantibiotic with antibacterial activity against Gram-positive pathogens. To probe the specificity of the biosynthetic pathway of mersacidin and obtain analogs with improved antibacterial activity, an efficient system for generating variants of this lantibiotic was developed. A saturation mutagenesis library of the residues of(More)
The generation of modified lantibiotics in whole cells has proved to be of value for the investigation of the specificity of the lantibiotic-processing enzymes and their tolerance to mutations in the primary sequence of lantibiotics. The development of methods to produce new lantibiotic variants has also enabled the investigation of the structure-activity(More)
Ammonium and asparagine produced a concentration-dependent reduction of cephamycin C biosynthesis by Streptomyces lactamdurans. Addition of ammonium salts at 1 mM concentration reduced cephamycin biosynthesis by resting cells of S. lactamdurans, whereas concentrations of asparagine above 10 mM were required to get the same effect. High ammonium(More)
The biosynthetic pathway of the type B lantibiotic actagardine (formerly gardimycin), produced by Actinoplanes garbadinensis ATCC31049, has been cloned, sequenced and annotated. The gene cluster contains the gene garA that encodes the actagardine prepropeptide, a modification gene garM, involved in the dehydration and cyclization of the prepeptide, several(More)