Elucidation of the function of two glycosyltransferase genes (lanGT1 and lanGT4) involved in landomycin biosynthesis and generation of new oligosaccharide antibiotics

Abstract

The high-yielding production of novel oligosaccharide antibiotics using glycosyltransferase gene cassettes generated in a very convenient way proves that glycosyltransferases can be flexible towards the alcohol substrate. In addition, our results indicate that LanGT1 from S. cyanogenus S136 is a D-olivosyltransferase, whereas LanGT4 is a L-rhodinosyltransferase.

Inactivation of gilGT, Encoding a C‐Glycosyltransferase, and gilOIII, Encoding a P450 Enzyme, Allows the Details of the Late Biosynthetic Pathway to Gilvocarcin V to be Delineated

“…The highest homologies were found with LanGT2 (38% amino-acid identity), a GT presumed to be involved in attaching the first D-olivose to landomycin aglycon, [13][14][15] and UrdGT2 (31% amino-acid identity), which is the C-GT of the urdamycin biosynthetic pathway. [16][17][18] The previously reported putative GilGT protein had 495 amino acids, which is approximately 120 amino acids longer than any other polyketide GT found so far.…”

Identification of the Function of Gene lndM2 Encoding a Bifunctional Oxygenase-Reductase Involved in the Biosynthesis of the Antitumor Antibiotic Landomycin E by Streptomyces globisporus 1912 Supports the Originally Assigned Structure for Landomycinone

“…S. globisporus strains were grown at 30 °C. Polyketide production of S. globisporus and S. fradiae strains was examined in SG and NL111v, respectively.5 , 8 For total and plasmid DNA isolation, streptomycete strains were grown in YEME for 48 h. 27 Solid oatmeal medium (OM) 8 was used for S. globisporus sporulation and plating of E. coli-Streptomyces matings. Where required, S. globisporus and E. coli strains were grown in the presence of ampicillin, apramycin, spectinomycin, kanamycin, chloramphenicol, nalidixic acid, and hygromycin at concentrations specified.…”

“…The PCR product has been sequenced and cloned into the pMUNII vector to give pMUN-lanMneu. Gene lanM2 was excised as 2.5-kb HindIII-XbaI fragment from pMUN-lanMneu and cloned into pUWL201 8 under the ermE* promoter (pUWLlanM2). It was also cloned as 2.9-kb PvuII fragment into pKC1218E (pKC1218ElanM2).…”

“…Therefore, previous experiments had been limited to the heterologous expression of selected biosynthetic genes in other polyketide-producing strains, such as the urdamycin A (3) producer S. fradiae TÜ 2717, which led to the identification of the glycosyltransferase genes lanGT1 and lanGT4 as D-olivosyl-and Lrhodinosyltransferases, respectively. 7,8 Only recently, successful initial gene inactivation experiments were performed in S. globisporus by intergeneric conjugation, 9 which further led to the identification of the function of a regulatory enzyme encoded by lndI 6 and the cyclases encoded by lndF and lndL ,10 which are both involved in the formation of the angucycline framework of landomycin E (1).…”

On the Acceptor Substrate of C‐Glycosyltransferase UrdGT2: Three Prejadomycin C‐Glycosides from an Engineered Mutant of Streptomyces globisporus 1912 ΔlndE(urdGT2)

“…[18] The overall structural and biosynthetic similarity between these two closely related sets of antibiotics allowed several successful combinatorial, biosynthetic gene-combination experiments, leading to new hybrid molecules. [5,6,15,[19][20][21][22][23][24] The most striking structural difference is that the trisaccharide chain found in the urdamycins is C-glycosidically linked at C9, while the oligosaccharide chains found in the different landomycins are O-glycosidically linked at the 8-position. The enzymes responsible for the first glycosyl transfer step for these chains, the glycosyl transferases (GT) UrdGT2 and LanGT2/LndGT2, are closely related.…”