*2.2. Marine Enterococcal Genomes Harbor Diverse Biosynthetic Gene Clusters (BGCs) Coding for Antimicrobial Compounds*

Two informatic packages, antiSMASH5 [57] and Bagel4 [58], accurately predict all known enterococcal bacteriocins whose properties have been well studied [32,33], including bacteriocin 31, bacteriocin T8, durancin Q, enterocin 96, enterocin1071A and 1071B, enterocin\_A, enterocin B, enterocin CRL35, enterocin EJ97, enterocin SE-K4, enterocin P, enterocin Xα and Xβ, enterolysin A, hiracin JM79, mundticin KS, and others. This also includes the *E. faecalis* cytolysin, a highly divergent two-component lantipeptide-type bacteriocin active against nearly all Gram positives [60], which also possesses lytic activity for some eukaryotic cells [61]. Therefore, antiSMASH5 [57] and Bagel4 [58] were used to mine the genomes of all 22 genomes for putative bacteriocin biosynthesis operons (Supplementary Table S3). This analysis identified one or more gene clusters encoding a bioactive compound precursor in each genome. In total, 73 antimicrobial compound BGCs were predicted, including 61 (83.56%) bacteriocins, 10 (13.70%) related to terpene synthesis, and 2 (2.74%) related to putative nonribosomal peptides (NRPs). The NRPs biosynthetic gene clusters were found only in *E. lactis* genome (MP10-1), whereas terpene BGCs were found among *E. casseliflavus* (HT1-1, J2, J4), *E. hirae* (C7, DMW1-1, MP1-1, MP1-2, MP1-4, MP1-5), and *E. mundtii* (MP7-18) species (Supplementary Table S3). NRP and terpene BGCs were predicted only by antiSMASH5 [57], whereas bacteriocins were identified by both tools.



106

penguin;

et al., 2020). 5 The enterococci species were confirmed by pairwise comparison of their average nucleotide identity (ANI) using as reference the following genomes:

ATCC14025;

*Enterococcus casseliflavus*

ATCC12755;

*Enterococcus faecalis*

ATCC19433;

*Enterococcus hirae* ATCC 9790;

*Enterococcus lactis* KCTC 21015;

*Enterococcus mundtii* ATCC 882.

ST—snowy-crowned

 tern;

DMW—dwarf

 minke whale; RD—Risso's dolphin, and B, C, J or L—South American fur seal. 4 Genomes sequenced in a previous study (Prichula

*Enterococcus avium*
