Abstract: The present invention relates to hybrid glycosylated products, and in particular, to natural products such as polyketides and glycopeptides, and to processes for their preparation. The invention is particularly concerned with recombinant cells in which a cloned microbial glycosyltransferase can be conveniently screened for its ability to generate specific glycosylated derivatives when supplied with polyketide, peptide, or polyketide-peptides as substrates. The invention demonstrates that cloned glycosyltransferases when rapidly screened for their ability to attach a range of activated sugars to a range of exogenously supplied or endogenously generated aglycone templates, show a surprising flexibility towards both aglycone and sugar substrates, and that this process allows the production of glycosylated polyketides in good yield.

Abstract: A bioactive compound, or family of compounds, is biosynthesised by a cell using a plurality of enzymic activities. Host cells are provided that substantially lack the bioactivity, but possess at least a first one of the enzymic activities (or nucleic acid encoding a corresponding enzyme). The cells are transformed with nucleic acid expressible to provide at least a second enzymic activity which enables the cells to produce a bioactive compound. A family of cells may be transformed with a multiplicity of different nucleic acids, leading to a library of cells including cells producing different bioactive product, and cells not producing bioactive products. Transformed cells may be screened for bioactivity. Active cells may be isolated and cultured, and bioactive compounds may be isolated.

Abstract: A polyketide synthase (“PKS”) of Type I is a complex multienzyme including a loading domain linked to a multiplicity of extension domains. The first extension module receives an acyl starter unit from the loading domain and each extension module adds a further ketide unit which may undergo processing (e.g. reduction). We have found that the Ksq domain possessed by some PKS's has decarboxylating activity, e.g. generating (substituted) acyl from (substituted) malonyl. The CLF domain of type II PKS's has similar activity. By inserting loading modules including such domains into PKS's not normally possessing them it is possible to control the starter units used.

Abstract: The rapamycin gene cluster is an example of a gene cluster which includes a gene (rapL) leading to the formation of a precursor compound (pipecolic acid, in this case) which is required for inclusion in the larger product (rapamycin) produced by the enzymes encoded by the cluster. We have produced a mutant strain containing a rapamycin gene cluster in which the rapL gene is disabled. The strain does not naturally produce rapamycin but does so if fed with pipecolic acid. By feeding with alternative carboxylic acids we have produced variants of rapamycins. Tests have shown biological activity.

Abstract: The present invention relates to Mycobacterium ulcerans virulence plasmid, pMUM001 and particularly to a cluster of genes carried by this plasmid that encode polyketide synthases (PKSs) and polyketide-modifying enzymes necessary and sufficient for mycolactone biosynthesis. More particularly this invention is directed to novel purified or isolated polypeptides, the polynucleotides encoding such polypeptides, processes for production of such polypeptides, antibodies generated against these polypeptides, the use of such polynucleotides and polypeptides in Diagnostic methods, kits, vaccines, therapy and for the production of mycolactone derivatives or novel polyketides by combinatorial synthesis.

Abstract: A hybrid type I polyketide synthase gene typically containing a starter module and a plurality of heterologous extender modules is used to synthesise novel polyketides. It is preferably under the control of type II polypolyketide synthase promoter e.g. act I or S.coelicolor.

Abstract: A polyketide synthase (“PKS”) of Type I is a complex multienzyme including a loading domain linked to a multiplicity of extension domains. The first extension module receives an acyl starter unit from the loading domain and each extension module adds a further ketide unit which may undergo processing (e.g. reduction). We have found that the Ksq domain possessed by some PKS's has decarboxylating activity, e.g. generating (substituted) acyl from (substituted) malonyl. The CLF domain of type II PKS's has similar activity. By inserting loading modules including such domains into PKS's not normally possessing them it is possible to control the starter units used.