Fig. 3

Diversity among the 13 representative members of the roseocin family. A Three common types of BGCs encode roseocin homologs, type-1, type-2, and type-3 BGC examples are of S. rhizosphericus, S. roseosporus NRRL 11379 and C. methinotrophica, respectively. B Phylogenetic tree of lanthipeptide core sequences with ML method with bootstrap values of 500 replicates. The exceptional third precursor (LanA2A) of the single LanM-three precursor i.e. type-1 BGC, is phylogenetically related to alpha peptides. Colour coding in Fig. 3B is red: alpha peptides; green: beta peptides; blue: third precursor core region. C and D Variation in the core peptide sequences as a function of Shannon entropy in the roseocin alpha and beta homologs, respectively. The alpha peptides contain a S/TxxxxTxGCC motif at the N-terminal end, and beta homologs contain a GS/TxxxxS/TxGCC motif at the C-terminal end. E A gigantic Rosα homolog from the Micromonosporaceae family contains nine Cys and thirteen Ser/Thr residues that may form as many lanthionine rings. Rosα of Streptomyces roseosporus (S. roseo) contains an indispensable disulphide bond and four (methyl)lanthionine rings (dotted lines depict the proposed ring topology in Rosα, Singh et al. 2020); M. arida-Micromonospora arida. LanA precursor peptide, LanM modification enzyme, HP Hypothetical Protein, LanT dual function peptidase-domain containing transporter