Shikonin Inhibited Growth and N-acetylation of 2-aminofluorene in Bacteria Strains Staphylococcus aureus and Klebsiella pneumoniae

紫草醌抑制金黃色葡萄球菌和肺炎克雷白氏菌的生長及二胺螢素的N-乙醯化作用

袁上雯(Shang-Wen Yuan) ； 鄒梅芬(Mei-Fen Tsou) ； 陳光偉(Guang-Wei Chen) ； 沈瑞隆(Jui-Lung Shen) ； 游春淑(Chun-Shu Yu) ； 鍾景光(Jing-Gung Chung)

《Mid-Taiwan Journal of Medicine》 8卷3期 (2003/09) Pp. 119-126

https://doi.org/10.6558/MTJM.2003.8(3).1

摘要

目的N-乙醯轉移酵素（NAT，N-acetyltransferase）的作用相當明確，它是芳香胺致癌物和藥物代謝的第一步驟。紫草醌（shikonin）在體內及體外實驗都發現會造成癌細胞計畫性死亡（apoptosis），以及抑制血管新生（angiogenesis）作用，而血管新生是癌細胞生長及發炎作用的重要步驟。因此，本研究目的是檢測紫草醌（shikonin）引響細菌的生長和N-乙醯化2-aminofluorene的量。
方法利用Beckman的分光光度計來測量650nm光譜吸光值來決定紫草對金黃色葡萄球菌及肺炎克雷白氏菌生長抑制的影響。芳香胺的N-乙醯轉移酵素活化物和二胺螢素是利用高效率液相層析法（HPLC，high pressure liquid chromatography）測量，金黃色葡萄球菌及肺炎克雷白氏菌是由病人身上收集培養。
結果用不同濃度的紫草醌作用在金黃色葡萄球菌及肺炎克雷白氏菌的胞質液和懸浮液，造成二胺螢素的N-乙醯化程度不同。研究結果顯示，紫草醌的濃度愈高，對細菌本身及其胞質液中二胺螢素的N-乙醯化作用的抑制愈顯著。紫草醌並能降低金黃色葡萄球菌及肺炎克雷白氏菌的NAT酵素的動能常數（apparent values of Km and Vmax）。
結論紫草醌能降低Km和Vmax的值，紫草醌有抑制細菌生長及芳香胺的N-乙醯轉移酵素活化物的作用。

關鍵字

二胺螢素 ； 肺炎克雷白氏菌 ； N-乙醯二胺螢素 ； 乙醯轉移酵素 ； 金黃色葡萄球菌 ； 紫草醌

並列摘要

Objectives. N-acetyltransferase (NAT) is the first step in the metabolism (N-acetylation) of arylamine carcinogens (2-aminofluorene) and drugs (sulfamethazine). Angiogenesis is critical for tumor growth and inflammation, and shikonin has been reported to inhibit angiogenesis and induce apoptosis in vivo and in vitro. Therefore, our objective was to investigate the effect shikonin has on growth and N-acetylation of 2-aminofluorene in bacteria.
Methods. In this study, growth inhibition of S. aureus and K. pneumoniae was determined by measuring absorbance by an optical density method (OD at 650 nm) using a Beckman Spectrophotometer (DU 6401). We examined arylamine N-acetyltransferase (NAT) activity in the bacteria S. aureus and K. pneu1I1oniae collected from patients and examined the levels of Nacetylation of 2-aminofluorene by high performance liquid chromatography.
Results. Shikonin elicited dose-dependent bacteriostatic activity in both examined bacteria cultures. Cytosols and suspensions of S. aureus and K. pneumoniae with and without specific concentrations of shikonin co-treatment showed different percentages of 2-aminofluorene acetylation. The data indicated that the decrease in N-acetylation of 2-aminofluorene was associated with increased levels of shikonin in both examined bacteria cytosols and intact cells. The apparent values of Km and Vmax decreased after co-treatment with 4 μM shikonin.
Conclusions. Shikonin induces inhibition of growth and inhibition of arylamine NAT activity (N-acetylation of 2-aminofluorene) in S. aureus and K. pneumoniae.

並列關鍵字

2-aminofluorene ； K. pneumoniae ； N-acetyl-2-aminofluorene ； N-acetyltransferase ； S. aureus ； shikonin