본 연구에서는 연안갯벌 갯지렁이(Perinereis aibuhitensis)에서 분리한 광염성 미생물, Bacillus sp. EBW4의 특성과 다양한 환경조건에서 유기물 분해능을 분석하였다. 16S rRNA 염기서열에 기초하여 동정한 결과, 균주 EBW4는 Bacillus hemicentroti $JSM076093^T$와 98.3%, Bacillus hwajinponensis SW-$72^T$와 97.96% 그리고 Bacillus algicoa $KMM3737^T$와 96.28%의 상동성을 보였다. EBW4의 생장 가능한 온도 범위는 $4-40^{circ}C$, 염분도 범위는 0-17%, pH 범위는 5-9로 나타나 EBW4는 광염성 균주로 밝혀졌다. EBW4의 세포막을 구성하는 주요 지방산으로는 anteiso $C_{15:0}$, iso $C_{16:0}$, anteiso $C_{17:0}$, iso $C_{14:0}$ 등으로 각각 48.2, 12.1, 11.6, 9.4% 비율로 나타났다. EBW4는 탄수화물, 단백질, 지방 등 다양한 고분자 유기물을 분해할 수 있는 DNase, amylase, protease, lipase 등의 효소 활성뿐만 아니라, alkaline phosphatase, esterase (C4), leucine arylamidase 그리고 ${alpha}$-chymotrypsin 효소활성도 가지고 있었다. 다양한 염분 농도 조건에서 합성폐수를 이용한 실험에서 EBW4은 조사한 모든 범위의 염분 조건에서도 유기물 분해능이 우수하였다.
In this study, euryhaline marine microorganism, Bacillus sp. strain EBW4 isolated from polychaete (Perinereis aibuhitensis) of Suncheon Bay was physiologically, biochemically and genetically characterized. Based on 16S rRNA sequence, EBW14 was found to share 98.25% similarity with Bacillus hemicentroti $JSM076093^T$, 97.96% similarity with Bacillus hwajinponensis SW-$72^T$ and 96.28% similarity with B. algicoa $KMM3737^T$, respectively. The temperature range for the growth of strain EBW4 was $4-40^{circ}C$, NaCl concentration range 0-17% and pH range pH 5-9, revealing that EBW4 was euryhaline bacterium. Major fatty acids in strain EBW4 were composed of anteiso $C_{15:0}$ (48.2%), iso $C_{16:0}$ (12.1%), anteiso $C_{17:0}$ (11.6%) and iso $C_{14:0}$ (9.4%). EBW4 was found to have DNase, amylase, protease and lipase for the degradation of macromolecules such as DNA, carbohydrates, proteins, lipids, etc. The enzyme activities of alkaline phosphatase, esterase (C4), leucine arylamidase and ${alpha}$-chymotrypsin were also found in strain EBW4. Analysis of the biodegradation ability of EBW4 for organic hydrocarbons under different salinity conditions using synthetic water waste revealed that EBW4 exhibited the ability to degrade organic hydrocarbons very quickly, suggesting strain EBW4 may be a good candidate for the application to various industries.
