臨床分離之Acinetobacter baumannii的蛋白表達譜分析

Protein expression profiled analysis in clinical isolated Acinetobacter baumannii

梁君琦(Chun-Chi Liang)

指導教授 ： 陳凌雲

中山醫學大學/醫學院/醫學研究所/碩士(2012年)

https://doi.org/10.6834/CSMU.2012.00073

摘要

鮑氏不動桿菌 Acinetobacter baumannii (A. baumannii)，為伺機性的細菌。近年來成為院內感染最嚴重的致病菌之一，對 carbapenems 類抗生素產生抗藥性機制的方式中以產生 Carbapenem-hydrolyzing class D β-lactamases (CHDLs) 分解抗生素為最主要的作用機制。然而 A. baumannii 菌種鑑別準確性及其產生的抗藥性基因如何影響細菌的機制為本研究所想要探討的目的。
本研究使用自動化細菌鑑定及藥敏試驗分析儀操作菌株分離鑑定及藥敏試驗的結果比使用傳統細菌鑑定及紙錠擴散試驗的結果更符合試驗數據的正確性及可信度。
以多重聚合酶連鎖反應分析 A. baumannii 菌體內的碳醯胺基酶基因 (Carbapenemases genes) 分佈的情形，發現 A. baumannii 內並不是每個菌株百分之百都有攜帶和 OXA-23、24、51、58 like group 相關的基因，而有些菌株所攜帶的 OXA-type gene 則是同時具有多種的形式。
藉由使用 SDS-PAGE 蛋白質電泳分析來表現 A. baumannii 的蛋白表達譜，觀察到在不同的菌種之間其蛋白模式會呈現許多各式各樣不同的狀態，且彼此之間是有極大的差異性。而在同種的菌種之間有些雖有小部份差異，但大部份均是呈現固定的蛋白模式。這些小部份差異可能是因細菌在對抗抗生素時造成細菌體內的 DNA 序列產生突變或是組織構型的改變，因而使得細菌的蛋白模式也發生變化。
在以 MIC 值、多重聚合酶連鎖反應、蛋白質電泳分析等結果的綜合分析中，發現隨著 A. baumannii 對 imipenem 的 MIC 值上升， A. baumannii 的 Protein pattern 於18 kDa -20 kDa的位置會逐漸減弱或消失。
綜合分析的結果觀察到隨著 A.baumannii 攜帶基因的各種變化形式，影響到抗藥性的產生及藥物最低抑制濃度值的增減，同時也會影響到細菌體內蛋白模式的改變。這種蛋白模式變化及所攜帶酵素基因呈現的形式，可提供未來研究抗藥性的相關機轉參考的方式。

關鍵字

鮑氏不動桿菌:多重聚合酶連鎖反應分析:蛋白質電泳分析

並列摘要

Acinetobacter baumannii (A. baumannii), an opportunity bacteria, has become one of the most serious nosocomial infections sources. Its resistance mechanism to carbapenems antibiotic functions mainly by producing carbapenem-hydrolyzing class D β-lactamases (CHDLs). The objective of present study is to understand the detection accuracy of A. baumannii strains and the mechanism of how the resistance genes effects bacteria.
Present study adopts automated bacterial identification and susceptibility testing of the instrument operating strains isolation identification and the results of susceptibility testing to cross validate our findings. This is more accurate and reliable than traditional approaches such as bacterial identification and disc diffusion test.
The observations of Multiplex polymerase chain reaction analysis show the distribution of bacteria in vivo carbon amide gene (Carbapenemases genes). Results suggests that not every strains carries OXA-23、24、51、58 like group genes and some of the strains carry OXA-type gene with multiple forms.
Through the use of SDS-PAGE protein electrophoresis to display the protein expression profiling of A. baumannii, findings indicates the protein patterns different strains are distinct. There are slight differences between same kinds of bacteria but most of them represent as fixed protein pattern. These slight differences may result from change of bacterial protein patterns and indirectly cause the DNA sequences mutation or the change of organizational structure during the bacteria against antibiotics.
The indicators of MIC values, multiplex polymerase chain reaction, and protein electrophoresis analysis show the increase of indicator of MIC may weaken the protein pattern of A. baumannii at 18 kDa -20 kDa position.
Our analysis shows the change of A.baumannii genes influences the level of drug resistance and drug minimum inhibitory concentration values and effects bacteria in vivo protein patterns change. These protein patterns change and the representation of enzymes gene can offer valuable information for future research on resistant relevant mechanisms.

並列關鍵字

Acinetobacter baumannii:Multiplex polymerase chain reaction analysis:protein electrophoresis

參考文獻

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