• 자연과학논문집
• /
• 제14권2호
• /
• pp.67-82
• /
• 2004

고염에서 자라는 원시 박테리아인 Halococcus agglomeratus에서 Thiol-specific antioxidant 활성을 보이는 분자량이 22-kDa인 향산화 단백질을 순수 분리 정제하여 향산화 활성의 특성을 조사하였다. 그 결과 진핵 세포의 Thiol-specific antioxidant protein (TSA of TPx)과 유사한 활성을 갖는 것을 확인 할 수 있었다. 정제된 Thiol-specific antioxidant protein 은 환원제로 thiol 성분을 갖는 비효소적 금속 촉매 산화계( $Fe^{3+}$, $O^2$, DTT 또는 2-mercatoethanol : thiol- MCO system)에 의하여 Glutamine Synthetase (GS)의 불활성화를 방어하고 Ascorbate 같은 nonthiol 성환원제를 갖는 금속 촉매 산화계 ( $Fe^{3+}$, $O^2$, Ascorbatenol: nonthiol- MCO system)에 의해서는 GS의 불활성화를 방어하지 못하였다. 이것은 환원형 thiol성분이 항산화 단백질의 항산화 활성에 전자 공여체로 요구되어 지기 때문이라고 판단된다. 이 단백질은 다른 TPx와는 다르게 100%의 활성을 나타내려면 NaCl의 농도가 500mM이상이 되어야 한다. 이상의 결과는 원시 박테리아에도 TPx가 존재하여 활성 산소종을 제거하는 생화학적 역할을 수행함을 시사하고 있다.

• 미생물학회지
• /
• 제29권1호
• /
• pp.56-62
• /
• 1991

Extremely halophilic bacteria isolated from salterns at Mado, Kyunggido, Korea, were identified and investigated on their salt requirements. The results have shown that six strains were identified to be belonged to the genus Halobacterium and three strains identified as the fenus Halococcus. Among them, the optimal NaCl concentration for growth of Halobacterium sp. EH10 was at 4.2M and no growth occurs below 2.0M NaCl. The strain, EH10, is nonmotile and showed acid production from glucose, fructose and maltose while H. salinarum is motile and does not produce acid from any carbohydrates. On the other hand, the strain EH10 does not utilize readily glucose while a number of sugars are readily utilized for growth with acid production by H. saccharovorum. Thus, the isolate, EH10, was classified into the genus Halobacterium and could be a novel species of the genus by its main morphological and physiological features including G+C content. The optimal temperature for growth of the isolate, EH10, was 50.deg.C. But this strain did not grow when NaCl was replaced with KCl.

• Journal of Microbiology and Biotechnology
• /
• 제16권10호
• /
• pp.1640-1645
• /
• 2006

We studied the diversity of the halophilic archaea and bacteria in crystallizer ponds of a Korean solar saltern by analyzing 16S rRNA gene libraries. Although diverse halophilic archaeal lineages were detected, the majority (56%) were affiliated with the uncultured and cultured Halorubrum group. Halophilic archaea that have been frequently observed in solar saltern environments previously, such as Halogeometricum, Halococcus, Haloarcula, and Haloferax, were not detected in our samples. The majority of clones (53%) belonged to the Cytophaga-Flavobacterium-Bacteroides and ${\alpha}-,\;{\gamma}-,\;and\;{\delta}-Proteobacteria$ groups, with 47% of the clones being affiliated with ${\gamma}-Proteobacteria$. We also identified new ${\delta}-Proteobacteria$-related bacteria that have not been observed in hypersaline environments previously. Our data show that the diversity of the halophilic archaea and bacteria in our Korean saltern differs from that of solar salterns found in other geographic locations. We also showed by quantitative real-time PCR analysis that bacteria can form a significant component of the microbial community in solar salterns.