modules that house repeated sets of functional domains, which
select, activate, and couple amino acids drawn from a pool of
nearly 500 potential building blocks (Walsh et al., 2013). Five
gene cluster involved in non-ribosomal synthesis of cyclic LP and
the iron-siderophore bacillibactin were identified in the genome
of FZB42 (Table 1). Three of the respective gene clusters were
assigned for synthesis of surfactin, fengycin, and bacillomycin
D. Bacillomycin D was identified as being the most powerful
antifungal metabolite in vitro produced by FZB42 (Figure 2).
The heptapeptide moiety of bacillomycin D, belonging to
the iturin family of cyclic LP, is attached to a β-amino fatty
acid chain of variable length (C14–C17). The peptide moiety
of the heptapeptide surfactin is linked to a β-hydroxyl fatty
acid (C12–C16), whilst the fengycin decapeptides are linked to
a β–hydroxyl fatty acid chain (C 14–C18). Their synthesis is
accomplished by multimodular peptide synthetases and depends
on a functional phospho-pantheinyl transferase (Sfp) which
transfers 4
- phosphopantetheine from coenzyme A to the carrier
proteins during non-ribosomal synthesis.