Baev Vesselin, Iliev Ivan, Apostolova Elena, Gozmanova Mariyana, Hristova Yana, Ilieva Yanitsa, Yahubyan Galina, Gochev Velizar
Department of Molecular Biology, Faculty of Biology, University of Plovdiv, Tzar Assen 24, 4000 Plovdiv, Bulgaria.
Department of Biochemistry and Microbiology, Faculty of Biology, University of Plovdiv, Tzar Assen 24, 4000 Plovdiv, Bulgaria.
Curr Issues Mol Biol. 2024 Aug 24;46(9):9359-9375. doi: 10.3390/cimb46090554.
The genus is renowned not only for its natural antibiotic production but also for its abundant chitinolytic enzymes, which break down stubborn chitin into chitooligosaccharides. Despite this, there have been limited studies utilizing whole-genome sequencing to explore the repertoire of chitin degradation and utilization genes in . A particularly compelling source of novel antimicrobials and enzymes lies in the microbiota of insects, where bacterial symbionts produce antimicrobials to protect against opportunistic pathogens and enzymes to adapt to the environment. In this study, we present the chitinolytic strain PMB5, isolated from the insectivorous (European mantis). Whole-genome sequencing revealed that PMB5 harbors a linear chromosome of 7,211,961 bp and a linear plasmid of 327,989 bp. The genome comprises 6683 genes, including 6592 protein-coding sequences and 91 RNA genes. Furthermore, genome analysis revealed 19 biosynthetic gene clusters covering polyketides, terpenes, and RiPPs, with 10 clusters showing significant gene similarity (>80%) to known clusters like antimycin, hopene, and geosmin. In the genome of PMB5, we were able to identify several antibiotic resistance genes; these included (resistance to phenicol), (resistance to macrolides), (resistance to aminocoumarin), / (resistance to macrolides), (resistance to aminocoumarin) and (resistance to beta-lactams). Additionally, three clusters displayed no similarity to known sequences, suggesting novel bioactive compound discovery potential. Remarkably, strain PMB5 is the first reported capable of thriving on a medium utilizing chitin as a carbon source, with over 50 chitin-utilizing genes identified, including five AA10 family LPMOs, five GH18 chitinases, and one GH19 chitinase. This study significantly enhances the genomic understanding of , a species previously underrepresented in research, paving the way to further exploration of the biotechnological potential of the species.
该属不仅以其天然抗生素的产生而闻名，还因其丰富的几丁质分解酶而闻名，这些酶能将顽固的几丁质分解为壳寡糖。尽管如此，利用全基因组测序来探索该属中几丁质降解和利用基因库的研究仍然有限。昆虫的微生物群是新型抗菌剂和酶的一个特别引人注目的来源，其中细菌共生体产生抗菌剂以抵御机会性病原体，并产生酶以适应环境。在本研究中，我们展示了从食虫螳螂（欧洲螳螂）中分离出的几丁质分解菌株PMB5。全基因组测序显示，PMB5拥有一条7,211,961 bp的线性染色体和一条327,989 bp的线性质粒。该基因组包含6683个基因，包括6592个蛋白质编码序列和91个RNA基因。此外，基因组分析揭示了19个生物合成基因簇，涵盖聚酮化合物、萜类化合物和核糖体合成和翻译后修饰肽（RiPPs），其中10个簇与已知簇如抗霉素、藿烯和土臭素具有显著的基因相似性（>80%）。在PMB5的基因组中，我们能够鉴定出几个抗生素抗性基因；这些基因包括cat（对氯霉素耐药）、erm（对大环内酯类耐药）、acm（对氨基香豆素耐药）、erm/tet（对大环内酯类耐药）、acm（对氨基香豆素耐药）和bla（对β-内酰胺类耐药）。此外，有三个簇与已知序列没有相似性，这表明有发现新型生物活性化合物的潜力。值得注意的是，菌株PMB5是首个被报道能够在以几丁质作为碳源的培养基上生长的该属菌株，已鉴定出超过50个几丁质利用基因，包括五个AA10家族的溶氧酶（LPMOs）、五个GH18几丁质酶和一个GH19几丁质酶。这项研究显著增强了对该属的基因组理解，该属在以前的研究中代表性不足，为进一步探索该物种的生物技术潜力铺平了道路。
