Annals of Biological Research
Abstract
Author(s): Shilpi Bhardwaj, Sourav Bhattacharya, Arijit Das, Muthusamy Palaniswamy and Jayaraman Angayarkanni
Streptokinase is one of the best investigated fibrinolytic proteins of microbial origin and finds its application as a
therapeutic. The enzyme is a single-chain polypeptide that exerts its fibrinolytic action indirectly by activating the
circulatory plasminogen. The present study aims at the molecular identification of streptokinase producing SK-6
isolate by partial 16S rDNA sequencing and determination of various cultural parameters favouring the
streptokinase production by the isolate under submerged fermentation. Effects of carbon and nitrogen supplements
along with physical parameters such as initial pH of the medium and incubation temperature were considered.
Streptokinase activity was determined by the casein digestion method, based on the amount of the liberated tyrosine
from digested casein. The SK-6 isolate was found to be closely related to Streptococcus dysgalactiae subsp.
equisimilis strain:A-yo with 99% sequence similarity. The 714 bp 16S rDNA nucleotide sequence was provided a
GenBank accession number KF312378. Glucose (1% w/v) and tryptone (1.5% w/v) when used as supplements
enhanced streptokinase production. Determination of the physical parameters revealed the optimum initial pH and
incubation temperature for streptokinase production to be 7.0 and 37Ã?â??Ã?°C respectively. The current findings clearly
denote that the cultural parameters have a profound effect on the production of streptokinase under submerged
fermentation.
