脉冲场凝胶电泳
PFEG(Plused-Field Gel Electrophoresis)技术是将细菌完全包裹在一种特殊的琼脂中,然后加入一些化学试剂,比如十二烷基肌氨酸钠,蛋白酶K等,将细菌中的蛋白成分全部溶化,消化,只剩下整个序列的DNA。经稀有限制性内切酶消化后,切割成大小不等的片断,然后将其置于脉冲场电泳槽中电泳,完成片段分离的过程。
经染色脱色后,在读胶仪上显现酶切后的电泳图谱,并经统计软件的分析,即可判断出条带的不同,同时做出细菌的同源性分析,从而达到分型的目的。其中能影响电泳图谱的参数很多,如电泳的转换时间,电泳的总时间,电泳的角度,电压,电泳液的温度等等,且不同的参数会得到不同的电泳图谱。
Pulsed Field Gel Electrophoresis Short Protocol
1. Reagents
1.1 Tris-EDTA Buffer (10mM Tris: 1mM EDTA, pH 8.0).
- 10ml of 1M Tris, pH 8.0
- 2ml of 0.5M EDTA, pH 8.0
- Dilute to 1000ml with molecular grade water.
1.2 Cell Suspension Buffer (CSB). (100mM Tris:100mM EDTA, pH 8.0).
- 10ml of 1M Tris, pH 8.0
- 20ml of 0.5M EDTA, pH 8.0
- Dilute to 100 ml with molecular grade water.
1.3 InCert agarose for plugs (1.6% InCert: 1% SDS agarose in TE).
- Weigh 0.8g InCert agarose into a 250 ml screw-cap flask
- Add 46.7 ml TE Buffer; swirl gently to disperse agarose.
- Microwave for 30 sec., mix gently and repeat for 10 sec.
- Place flask in 55-60℃ water bath for 5 min before adding SDS.
- Add 2.5 ml of 20% SDS and mix well.
- Keep at 55-60oC water bath until ready to use.
1.4 Cell Lysis Buffer (50mM Tris:50mM EDTA, pH, 8.0 + 1% Sarcosine).
- 25 ml of 1M Tris, pH 8.0
- 50ml of 0.5M EDTA, pH 8.0
- 50ml of 10% N-Lauryl Sarcosine.
- Dilute to 500 ml with sterile type 1 water.