Pranav Parameswaran Sree, Mahalakshmi Balasubramanian, Sivakumar Ramamoorthy, Karthikeyan Raman, Rajendhran Jeyaprakash
Department of Genetics, School of Biological Sciences, Madurai Kamaraj University, Madurai, India.
Curr Microbiol. 2021 Apr;78(4):1168-1176. doi: 10.1007/s00284-021-02393-0. Epub 2021 Feb 22.
The increased prevalence of multidrug-resistant pathogens poses a significant clinical threat, and hence, the discovery of novel antibiotics is the need of the hour. Several attempts are being made worldwide to screen and identify newer antibiotics from various microbial sources. The genus Paenibacillus is known for its biosynthetic potential and metabolic versatility in producing several secondary metabolites. In this study, we isolated Paenibacillus alvei strain JR949 from the soil, which exhibited antimicrobial activity against Enteropathogenic Escherichia coli (EPEC), Pseudomonas aeruginosa (PAO1), and methicillin-resistant Staphylococcus aureus (MRSA). The whole genome of this strain was sequenced using the Illumina platform. The genome mining of the draft genome sequence revealed a total of 31 biological gene clusters (BGCs) responsible for the synthesis of secondary metabolites. The construction of the similarity network of the BGCs and the comparative analysis with the genetically related strains aided the identification of metabolites produced by this strain. We identified BGCs coding for paenibactin, paenibacterin, anabaenopeptin NZ857, icosalide A/B, polymyxin, and bicornutinA1/A2 with 100% similarity. The BGCs with lower sequence similarity to paenibacterin, polymyxin B, colistin A/B, pellasoren, tridecaptin, pelgipeptin, and marthiapeptide were also identified. Furthermore, 13 putative NRPS BGCs, 3 NRPS-T1PKS hybrid clusters, a T1PKS, and a bacteriocin BGC were identified with very low similarity (≤ 25%) or no similarity with known antibiotics. Further experimental investigations may result in the discovery of novel antimicrobial drugs.
多重耐药病原体患病率的增加构成了重大的临床威胁，因此，发现新型抗生素是当务之急。世界各地正在进行多项尝试，从各种微生物来源中筛选和鉴定新型抗生素。芽孢杆菌属以其生物合成潜力和在产生多种次级代谢产物方面的代谢多样性而闻名。在本研究中，我们从土壤中分离出了蜂房芽孢杆菌菌株JR949，该菌株对肠致病性大肠杆菌（EPEC）、铜绿假单胞菌（PAO1）和耐甲氧西林金黄色葡萄球菌（MRSA）具有抗菌活性。使用Illumina平台对该菌株的全基因组进行了测序。对草图基因组序列的基因组挖掘揭示了总共31个负责次级代谢产物合成的生物基因簇（BGC）。构建BGC的相似性网络并与遗传相关菌株进行比较分析，有助于鉴定该菌株产生的代谢产物。我们鉴定出编码蜂房菌素、芽孢杆菌素、鱼腥藻肽NZ857、二十烷酸内酯A/B、多粘菌素和双角菌素A1/A2的BGC，相似度为100%。还鉴定出与芽孢杆菌素、多粘菌素B、粘菌素A/B、pellasoren、十三肽菌素、pelgipeptin和玛氏肽序列相似性较低的BGC。此外，还鉴定出13个假定的非核糖体肽合成酶BGC、3个非核糖体肽合成酶-Ⅰ型聚酮合酶杂交簇、1个Ⅰ型聚酮合酶和1个细菌素BGC，它们与已知抗生素的相似性非常低（≤25%）或无相似性。进一步的实验研究可能会发现新型抗菌药物。
