title: Structure and tRNA Specificity of MibB, a Lantibiotic Dehydratase from Actinobacteria Involved in NAI-107 Biosynthesis.
abstract: Class I lantibiotic dehydratases dehydrate selected Ser/Thr residues of a precursor peptide. Recent studies demonstrated the requirement of glutamyl-tRNA(Glu) for Ser/Thr activation by one of these enzymes (NisB) from the Firmicute Lactococcus lactis. However, the generality of glutamyl-tRNA(Glu) usage and the tRNA specificity of lantibiotic dehydratases have not been established. Here we report the 2.7-Å resolution crystal structure, along with the glutamyl-tRNA(Glu) utilization of MibB, a lantibiotic dehydratase from the Actinobacterium Microbispora sp. 107891 involved in the biosynthesis of the clinical candidate NAI-107. Biochemical assays revealed nucleotides A73 and U72 within the tRNA(Glu) acceptor stem to be important for MibB glutamyl-tRNA(Glu) usage. Using this knowledge, an expression system for the production of NAI-107 analogs in Escherichia coli was developed, overcoming the inability of MibB to utilize E. coli tRNA(Glu). Our work provides evidence for a common tRNA(Glu)-dependent dehydration mechanism, paving the way for the characterization of lantibiotics from various phyla.
authors.affiliation: Department of Biochemistry; University of Illinois at Urbana-Champaign, Roger Adams Laboratory, 600 S. Mathews Ave., Urbana IL, 61801, USA.
authors.forename: Manuel A
authors.initials: MA
authors.lastname: Ortega
authors.affiliation: Department of Biochemistry; University of Illinois at Urbana-Champaign, Roger Adams Laboratory, 600 S. Mathews Ave., Urbana IL, 61801, USA.
authors.forename: Yue
authors.initials: Y
authors.lastname: Hao
authors.affiliation: Department of Chemistry and Howard Hughes Medical Institute; University of Illinois at Urbana-Champaign, Roger Adams Laboratory, 600 S. Mathews Ave., Urbana IL, 61801,USA.
authors.forename: Mark C
authors.initials: MC
authors.lastname: Walker
authors.affiliation: NAICONS Srl, Viale Ortles 22/4, 20139 Milan Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Donadio
authors.affiliation: NAICONS Srl, Viale Ortles 22/4, 20139 Milan Italy.
authors.forename: Margherita
authors.initials: M
authors.lastname: Sosio
authors.affiliation: Department of Biochemistry; University of Illinois at Urbana-Champaign, Roger Adams Laboratory, 600 S. Mathews Ave., Urbana IL, 61801, USA.|Center for Biophysics and Computational Biology; University of Illinois at Urbana-Champaign, Roger Adams Laboratory, 600 S. Mathews Ave., Urbana IL, 61801, USA.
authors.forename: Satish K
authors.initials: SK
authors.lastname: Nair
authors.affiliation: Department of Biochemistry; University of Illinois at Urbana-Champaign, Roger Adams Laboratory, 600 S. Mathews Ave., Urbana IL, 61801, USA.|Department of Chemistry and Howard Hughes Medical Institute; University of Illinois at Urbana-Champaign, Roger Adams Laboratory, 600 S. Mathews Ave., Urbana IL, 61801,USA.
authors.forename: Wilfred A
authors.initials: WA
authors.lastname: van der Donk
mesh_terms: D039903:Actinobacteria / Q000166:cytology / Q000201:enzymology*; D001430:Bacteriocins / Q000096:biosynthesis / Q000737:chemistry / Q000378:metabolism*; D006836:Hydro-Lyases / Q000737:chemistry* / Q000378:metabolism*; D008958:Models, Molecular; D008968:Molecular Conformation; D012343:RNA, Transfer / Q000737:chemistry* / Q000378:metabolism*; D013379:Substrate Specificity
chemical_list: D001430:Bacteriocins; C528150:microbisporicin; D012343:RNA, Transfer; D006836:Hydro-Lyases