국립 부경대학교

부경대학교(총장 장영수) 학부생의 논문이 해양의약 분야 국제학술지 <Marine drugs>에 게재돼 눈길을 끈다.

부경대 화학과 4학년 이영훈 학생은 최근 논문 ‘얼음 결합 단백질을 이용한 알코올 탈수소화효소의 빙결 저항(Protection of Alcohol Dehydrogenase against Freeze-thaw Stress by Ice-Binding Proteins is Proportional to their Ice-Recrystallization Inhibition Property)’(지도교수 김학준)을 이 학술지에 제1 저자로 게재했다.

<Marine drugs>는 스위스의 대형출판사 MDPI가 발행하는 인용지수(IF) 4.073의 SCI급 국제학술지다.

이영훈 학생은 이 논문에서 얼음 결합 단백질을 이용해 효소에 빙결 저항성을 부여하는 연구 결과를 밝혀 관심을 모았다.

얼음 결합 단백질은 극지에 서식하는 생물들에 주로 존재하는 단백질이다. 얼음 결정이 형성되는 것을 막아 어는 데 내성을 가지는 단백질이다. 이 단백질을 이용하면 다양한 물질에 냉동 저항성을 줄 수 있어 여러 번 얼리고 녹이더라도 물질의 특성을 보존할 수 있다.

이영훈 학생은 이번 연구에서 얼음 재결정 저항성이 다른 두 가지 얼음 결합 단백질과 알코올 탈수소화효소를 반복적으로 얼리고 녹이면서 형광물질인 ANS를 이용해 구조변화를 관찰했다.

연구 결과 얼음 재결정 저항성이 높은 얼음 결합 단백질일수록 빙결-해동에 따른 구조변화가 작고, 일반적인 단백질인 ADH는 구조변화가 비교적 큰 것으로 나타났다.

특히 활성을 실용적으로 보존하는 얼음 결합 단백질의 농도도 알아냈다. 알코올 탈수소화효소와 얼음 결합 단백질의 농도를 변화시켜가며 알코올 탈수소화효소의 활성 변화를 측정한 결과, 얼음 재결정 저항성이 높은 얼음 결합 단백질(LeIBP)을 500 µg/ml 이상의 농도로 사용했을 때 유의미한 효과가 있다는 것을 밝혔다.

그는 “이번 연구로 단백질을 냉동하고 해동하는 과정에서 활성을 최대한 보존할 수 있는 얼음 결합 단백질의 종류와 농도를 알아낼 수 있었다. 연구 결과를 약품이나 식품 등의 다른 다양한 단백질의 냉동 보관법에 적용할 수 있도록 후속 연구를 계속할 계획이다.”라고 말했다. <부경투데이>

Thesis of an undergraduate student at PKNU, published in an international journal <Marine drugs>
A study on anti-freezing proteins using 'ice binding protein' in antarctica living organisms

The thesis by an undergraduate student at Pukyong National University (President Jang Young-soo) was published in <Marine drugs>, an international academic journal in the field of marine medicine, attracting the public's attention.

Lee Young-hoon, a 4th grade student in the Department of Chemistry at Pukyong National University, recently published the paper ‘Protection of Alcohol Dehydrogenase against Freeze-thaw Stress by Ice-Binding Proteins is Proportional to their Ice-Recrystallization Inhibition Property’ (advisory prof. Kim Hak-jun) in this journal as the first author.

<Marine Drugs> is an SCI-level international academic journal with a citation index (IF) of 4.073 issued by MDPI, a large Swiss publishing company.

In this paper, Lee Young-hoon drew attention by revealing the results of a study that lends Freeze-thaw Stress to enzymes using ice-binding proteins.

Ice binding proteins are proteins that are mainly present in antarctica living organisms. It is a protein that is resistant to freezing by preventing the formation of ice crystals. If this protein is used, it can provide freezing-thaw stress against various substances, so even if it is frozen and thawed several times, the properties of the substance can be preserved.

In this study, Lee Young-hoon repeatedly frozen and melted two ice-binding proteins with different resistance to recrystallization of the ice and alcohol dehydrogenase. Then he observed the structural change using the fluorescent material ANS.

As a result of the study, it was found that the ice-binding protein with high resistance to recrystallization of the ice has less structural change due to freezing-thawing, and the general protein ADH has a relatively large structural change.

In particular, the concentration of ice-binding protein that practically preserves the activity was also found. As a result of measuring the activity change of alcohol dehydrogenase by varying the concentration of alcohol dehydrogenase and ice-binding protein, it was found that there is a significant effect when ice-binding protein (LeIBP) with high resistance to ice recrystallization was used at a concentration of 500 µg/ml or more.

He said, "Through this study, I was able to find out the types and concentrations of ice-binding proteins that can preserve their activity as much as possible in the process of freezing and thawing proteins. I plan to continue my follow-up studies so that my findings can be applied to the cryopreservation method of a variety of other proteins such as drugs and food." <Pukyong today>