Laboratory of Molecular Bacteriology, Department of Microbiology, University of Calcutta, 35, Ballygunge Circular Road, Kolkata, 700019, India.
Department of Chemical, Biological & Macro-Molecular Sciences, S. N. Bose National Centre for Basic Sciences, Block-JD, Sector-III, Salt Lake, Kolkata, 700106, India.
Appl Biochem Biotechnol. 2022 Aug;194(8):3333-3350. doi: 10.1007/s12010-022-03854-3. Epub 2022 Mar 14.
The natural and synthetic rubber (NR and SR) products are made up of poly-cis-isoprene which are estimated as one of the major solid-wastes and need to be cleared through bacterial bioremediation. The present research reports isolation and characterization of a gram-positive, non-spore forming, filamentous actinomycete Nocardia sp. BSTN01 from the waste of a rubber processing industry. We found NR- and SR-dependent growth of BSTN01 over a period of time. BSTN01 has been found to degrade NR by 55.3% and SR by 45.9% in 6 weeks. We have found an increase in the total protein of BSTN01 cells up to 623.6 and 573.9 µg/ml for NR and SR, respectively, after 6 weeks of growth in rubber-supplemented MSM medium. Scanning electron microscopy revealed adhesive growth of BSTN01 on the surface of NR and SR. Formation of aldehyde groups due to the degradation was indicated by Schiff's test and confirmed by FTIR-ATR analysis. The genome sequence of BSTN01 revealed the gene responsible for rubber degradation. The presence of lcp gene and structural analysis of the latex clearing protein further confirmed the reliability. Studies on quantification of rubber degradation capability by the isolated strain prove it to be an efficient degrader of NR and SR. This study revealed the genome sequence and structural analysis of the proteins responsible for degradation of rubber. A new fast-growing Nocardia strain can degrade both NR and SR with higher efficiency and have future potential for rubber solid-waste management either alone or in consortia.
天然橡胶（NR）和合成橡胶（SR）制品由聚顺式异戊二烯组成，这些制品被认为是主要的固体废物之一，需要通过细菌生物修复来清除。本研究报告了从橡胶加工工业废物中分离和鉴定出一种革兰氏阳性、非孢子形成、丝状放线菌诺卡氏菌 BSTN01。我们发现 BSTN01 可以在一段时间内依赖 NR 和 SR 生长。BSTN01 在 6 周内可将 NR 降解 55.3%，SR 降解 45.9%。我们发现 BSTN01 细胞的总蛋白分别增加了 623.6 和 573.9µg/ml，这是在添加橡胶的 MSM 培养基中生长 6 周后的结果。扫描电子显微镜显示 BSTN01 在 NR 和 SR 表面的黏附生长。Schiff 试验表明降解导致醛基形成，并通过傅里叶变换衰减全反射（FTIR-ATR）分析得到证实。BSTN01 的基因组序列揭示了负责橡胶降解的基因。lcp 基因的存在和乳胶清除蛋白的结构分析进一步证实了这一点。对分离菌株橡胶降解能力的定量研究证明其是 NR 和 SR 的有效降解菌。本研究揭示了负责橡胶降解的基因的基因组序列和结构分析。一种新的快速生长的诺卡氏菌菌株可以更有效地降解 NR 和 SR，并具有在单独或联合处理橡胶固体废物方面的未来潜力。
