Department of Microbiology, School of Sciences, Block-1, JAIN (Deemed To-Be University), 18/3, 9th Main Road, 3rd Block, Jayanagar, Bengaluru, 560011, Karnataka, India.
Sci Rep. 2021 Mar 18;11(1):6192. doi: 10.1038/s41598-021-84949-5.
L-Asparaginase is a therapeutically and industrially-competent enzyme, acting predominantly as an anti-neoplastic and anti-cancerous agent. The existing formulations of prokaryotic L-asparaginase are often toxic and contain L-glutaminase and urease residues, thereby increasing the purification steps. Production of L-glutaminase and urease free L-asparaginase is thus desired. In this research, bioprospecting of isolates from the less explored class Agaricomycetes was undertaken for L-asparaginase production. Plate assay (using phenol red and bromothymol blue dyes) was performed followed by estimation of L-asparaginase, L-glutaminase and urease activities by Nesslerization reaction for all the isolates. The isolate displaying the desired enzyme production was subjected to morphological, molecular identification, and phylogenetic analysis with statistical validation using Jukes-Cantor by Neighbour-joining tree of Maximum Likelihood statistical method. Among the isolates, Ganoderma australe GPC191 with significantly high zone index value (5.581 ± 0.045 at 120 h) and enzyme activity (1.57 ± 0.006 U/mL), devoid of L-glutaminase and urease activity was selected. The present study for the first-time reported G. australe as the potential source of L-glutaminase and urease-free L-asparaginase and also is one of the few studies contributing to the literature of G. australe in India. Hence, it can be postulated that it may find its future application in pharmaceutical and food industries.
L-天冬酰胺酶是一种具有治疗和工业应用价值的酶，主要作为一种抗肿瘤和抗癌药物。现有的原核 L-天冬酰胺酶制剂通常具有毒性，并含有 L-谷氨酰胺酶和脲酶残留，从而增加了纯化步骤。因此，需要生产无 L-谷氨酰胺酶和脲酶的 L-天冬酰胺酶。在这项研究中，对来自探索较少的担子菌纲 Agaricomycetes 类的分离物进行了生物勘探，以生产 L-天冬酰胺酶。进行了平板检测（使用苯酚红和溴百里酚蓝染料），然后通过 Nessler 化反应对所有分离物的 L-天冬酰胺酶、L-谷氨酰胺酶和脲酶活性进行了估计。显示所需酶生产的分离物进行了形态学、分子鉴定和系统发育分析，并使用基于最大似然统计方法的邻接法的 Jukes-Cantor 进行了统计验证。在分离物中，选择了具有显著高带指数值（120 小时时为 5.581±0.045）和酶活性（1.57±0.006 U/mL）的赤芝 GPC191，且不含 L-谷氨酰胺酶和脲酶活性。本研究首次报道了赤芝是无 L-谷氨酰胺酶和脲酶的 L-天冬酰胺酶的潜在来源，也是为数不多的对印度赤芝文献有贡献的研究之一。因此，可以推断它可能在制药和食品工业中找到未来的应用。
