## 3 Results and Discussion
### Analysis of Plasmid Presence and Antibiotic Resistance Genes
#### 3.6.5 NRPS and PKS Gene Clusters
Nearly all genes involved in the biosynthesis of the enediyne core, including the characteristic 1,5-diyne-3-ene motif of the 9-membered enediyne rings, are located upstream of protein XIJ15814.1 [63; 64; 65; 66]. We have designated these genes as EneE to EneE11. A notable observation is the absence of KedF and KedJ, essential genes for kedarcidin, in this enediyne cluster. Given the possibility of antiSMASH misprediction at the BGC boundary, as previously observed in JNUCC 0626 BGC7, we extended our analysis downstream of protein XIJ15834, which revealed the presence of both KedF- and KedJ-like proteins, along with a sugar biosynthetic gene cluster. The additional genes have been designated using kedarcidin nomenclature, including EneF, EneS5, EneS12, EneS7, EneS2, EneR6, EneJ, EneE, EneS, EneU1, and EneU2. Ultimately, the enediyne BGC in _Lentzea_ sp. JNUCC 0626 is composed of 38 proteins, spanning from protein XIJ15812 to protein XIJ15845, and is predicted to produce an enediyne core conjugated with a carbohydrate. However, the genes involved in the biosynthesis of Sporolide's cyclohexenone moiety, kedarcidin's naphthalene moiety, or \(\beta\)-azatyrosine were not detected. Further studies involving natural product isolation will be necessary to explore the potential presence of new moieties in the _Lentzea_ sp. JNUCC 0626 enediyne and its connection to the siderophore structure of the first BGC (Figure 7, Table S22). BGC Region 9 Derived from _Lentzea_ sp. JNUCC 0626  
The BGC region 9 of _Lentzea_ sp. JNUCC 0626 comprises several key components, as illustrated in Figure S14 and detailed in Table S23. This region includes one NRPS/PKS (protein XIJ15997), a Type I PKS consisting of KR and AT domains (protein XIJ16012), and two NRPSs (proteins XIJ16010 and XIJ16011). Additionally, it harbors over five regulatory genes of various types and more than three transporter proteins. Furthermore, region 9 features proteins characteristic of typical NRPS/PKS hybrid structures, including thioesterases (proteins XIJ15993 and XIJ16009), 3-oxoacyl-ACP synthase III (KAS III, proteins XIJ15991, XIJ16017, and XIJ16018), ACP (protein XIJ16020), MbtH family NRPS accessory protein (protein XIJ16015), and methylmalonyl-CoA epime  
Figure 7: Genetic organization of the enediyne gene cluster from BGC region 8 in JNUCC 0626. This gene cluster consists of over 38 genes, including enediyne core genes, sugar biosynthesis genes, 6 regulatory genes, and 1 transporter gene. However, further experimental validation is required. BGC Region 10 Derived from _Lentzea_ sp. JNUCC 0626  
The BGC region 10 of _Lentzea_ sp. JNUCC 0626 comprises a hybrid gene cluster of Type I and Type III polyketide synthases. As shown in Table 3, bioinformatic analyses reveal that this region is related to known hybrid polyketides, such as kendomycin and venemycin [67; 68; 69]. Specifically, it includes a Type I PKS composed of two modules (XJI19096), one module (XJI16064), and three modules (XJI16078), along with the biosynthetic enzymes for 3,5-dihydroxyboxbenzoic acid (DpgA, DpgB, DpgC, and DpgD). Notably, an additional protein consisting of two modules and 2881 amino acids is located just downstream of XJI19096, but it could not be found in the GenBank data (see Figure S15 and Table S24). We hypothesize that the biosynthesis of the Type I PKS in region 10 begins with the formation of 3,5-dihydroxyboxbenzoic acid derivatives catalyzed by enzymes encoded by genes XJI16057, XJI16058, XJI16059, and XJI16076. These enzymes are homologous to DpgA-DpgD and are proposed to catalyze the formation of the 3,5-dihydroxyboxbenzoic acid starter unit utilized by the Type I modular PKS for biparylpolyketide synthesis in _Lentzea_ sp. JNUCC 0626 [70]. The XJI16059 protein shares 65.6% and 68.0% identity with VemA and Ken2, respectively, which are Type III PKSs that catalyze the conversion of four malonyl-CoA molecules to (3,5-dihydroxyboxphenyl)acetyl-CoA in the BGCs of _Streptomyces_ sp. S006 and _Streptomyces violacoruber_.