In vitro characterization of jellyfish venom fibrin(ogen)olytic enzymes from Nemopilema nomurai

 

Seong Kyeong Bae¹, Hyunkyoung Lee⁴, Yunwi Heo³, Min Jung Pyo¹, Indu Choudhary¹, Chang Hoon Han², Won Duk Yoon², Changkeun Kang¹, Euikyung Kim^1 4

 

1 College of Veterinary Medicine, Gyeongsang National University, Jinju 660-701, Korea.

2 Headquarters for Marine Environment, National Fisheries Research & Development Institute, Shiran-ri, Gijang-eup, Gijang-gun, Busan 619-705, Korea.

3 Gyeongnam Department of Environment & Toxicology, Korea Institute of Toxicology, Gyeongnam 52834, Jinju, Korea.

4 Institute of Animal Medicine, Gyeongsang National University, Jinju, 660-701, Korea.

 

ABSTRACT

Background:

Because jellyfish are capable of provoking envenomation in humans, they are considered hazardous organisms. Although the effects of their toxins are a matter of concern, information on the venom components, biological activity and pathological mechanisms are still scarce. Therefore, the aim of the present study was to investigate a serine protease component of Nemopilema nomurai jellyfish venom (NnV) and unveil its characteristics.

 

Methods:

To determine the relationship between fibrinolytic activity of NnV and the serine protease, fibrin zymography was performed using metalloprotease and serine protease inhibitors. The biochemical characterization of serine proteases of NnV were determined by the amidolytic assay. Fractions with fibrinolytic activity were obtained by DEAE cation exchange column.

 

Results:

NnV displayed fibrinolytic activities with molecular masses of approximately 70, 35, 30, and 28 kDa. The fibrinolytic activity of NnV was completely obliterated by phenylmethylsulfonyl fluoride, a prototype serine protease inhibitor. Based on amidolytic assays using chromogenic substrates specific for various kinds of serine proteases, NnV predominantly manifested a chymotrypsin-like feature. Its activity was completely eliminated at low pH (< 6) and high temperatures (> 37 °C). Some metal ions (Co²⁺, Cu²⁺, Zn²⁺ and Ni²⁺) strongly suppressed its fibrinolytic activity, while others (Ca²⁺ and Mg²⁺) failed to do so. Isolation of a serine protease with fibrionolytic activity from NnV revealed that only p3 showed the fibrinolytic activity, which was completely inhibited by PMSF.

 

Conclusion:

The present study showed that N. nomurai jellyfish venom has a chymotrypsin-like serine protease with fibrinolytic activity. Such information might be useful for developing clinical management of jellyfish envenomation and pharmacological agents with therapeutic potential for thrombotic diseases in the future.

 

Keywords: Nemopilema nomurai; Jellyfish venom; Chymotrypsin; Serine protease; Fibrinolytic activity

 

Received: February 15, 2017.

Accepted: July 03, 2017.

 

Correspondence: ekim@gnu.ac.kr

 

Authors’ contributions

EK conceived and designed the study. SKB and HL mainly performed the experiments and wrote the manuscript. SKB and HL contributed equally to this work. MJP, YH and IC analyzed the data. CHH, WDY and CK interpreted and discussed the data. All authors have read and approved the final manuscript.

 

Competing interests

The authors declare that they have no competing interests.