l-asparaginase production in the pseudomonas pseudoalcaligenes strain jhs-71 isolated from jooshan hot-spring

l-asparaginase has lots of medical and industrial applications. ever since l-asparaginase anti-tumor activity was first demonstrated, its production using microbial systems has attracted considerable attention owing to their cost-effective and eco-friendly nature. the aim of this study is to obtain l-asparaginase producing bacteria and determining the enzyme activity. samples were picked up from jooshan hot springs located in the sirch, kerman. the l-asparaginase producing bacteria were screened on the agar medium supplied with l-asparagine and phenol red indicator dye (ph-7.0). l-asparaginase activity was detected on the basis of pink color around the colony. enzyme production was also performed based on ammonia detection by nessler method. among 24 strains, there were 7 strains which could produce l-asparaginase.sequencing of 16s rrna showed that, the best isolates producing l-asparaginase belongs to the pseudomonas genus. enzyme activity after 24 and 48 h of incubation showed that pseudomonas pseudoalcaligenes strain jhs-71was the best strain that produced l-asparaginase about 240 (u/ml) after 48h of incubation. results showed that, l-asparaginase activity enhanced about 27% in the presence of co+2. l-asparaginase jhs-71 retained more than 50% of its initial activity in the presence of cu+2, mn+2, zn+2, mg+2 and fe+2. because of various applications of l-asparaginase in biotechnology, p. pseudoalcaligenes strain jhs-71 can be used as a suitable candidate in these fields.