Bacterial transformation

 

Introduction

Transformation is the process of introducing foreign DNA (e.g plasmids, BAC) into a bacterium. Bacterial cells into which foreign DNA can be transformed are called competent . Some bacteria are naturally competent (e.g B. subtilis ), whereas others such as E. coli are not naturally competent. Non-competent cells can be made competent and then transformed via one of two main approaches; chemical transformation and electroporation .

There are advantages and disadvantages to both transformation methods. In general, chemical transformation is less prone to error and faster however electroporation produces a higher transformation efficiency (fraction of transformed cells that actually uptake the foreign DNA). See Molecular Cloning for a fuller discussion of both approaches.

Protocols

OpenWetWare already has a number of protocols relating to bacterial transformation but more are always welcome .

If you use a variant on one of these protocols please feel free to add a link to your protocol from one of these pages so other users can find a protocol that works for them. Additionally, if anyone uses the Innoe or Hanahan high-efficiency protocols, then please add protocols here.

Chemical transformation

If you plan on doing a chemical transformation, then you should see these pages -

• Preparing chemically competent cells
• Preparing TSS buffer
• Transforming chemically competent cells
• Preparing chemically competent cells (Inoue)
• Transforming chemically competent cells (Inoue)
• TOP10 chemically competent cells

Chemical transformation buffer comparison

Someone should check out the claims of Nishimura90. tk 08:58, 25 September 2007 (EDT)

Rubidium chloride transformation protocol here

Someone should check the claims of 1e10 chemical competence using 10% ethanol and calcium chloride protocols here.

Electroporation

If you plan on using electroporation, then see these pages -

• Electrocompetent cells
• Electroporation