SOB

(Difference between revisions)

Latest revision as of 02:13, 31 May 2008

SOB Medium. Used in growing bacteria for preparing chemically competent cells

Per liter:

Notes:

Some formulations of SOB use 10 mM MgCl₂ and 10 mM MgSO₄ instead of 20 mM MgSO₄.
SOB medium is also available dry premixed from Difco, 0443-17.
Adjust to pH 6.8-7.0 prior to use. This requires approximately 25 ml of 1M NaOH per liter.
MgSO₄ should be autoclaved separately and added just before use.

Growth of competent TOP10 cells in Example 2 of the Bloom05 patent is performed in 15/10 broth, which is similar to SOB:

Adapted From:

F. Ausubel et al., Short Protocols in Molecular Biology (John Wiley & Sons, ed. 4, 1999) pg. A1-36

SOB supposedly stands for super optimal broth.

@@ Line 7: / Line 7: @@
 *10 mM NaCl
 *2.5 mM KCl
-*20 mM MgSO<sub>4</sub>
+*1M MgSO<sub>4</sub>
 Per liter:
@@ Line 16: / Line 16: @@
 *120.4g MgSO<sub>4</sub>
-''Note:'' Some formulations of SOB use 10 mM MgCl<sub>2</sub> and 10 mM MgSO<sub>4</sub> instead of 20 mM MgSO<sub>4</sub>.
+''Notes:''
+:* Some formulations of SOB use 10 mM MgCl<sub>2</sub> and 10 mM MgSO<sub>4</sub> instead of 20 mM MgSO<sub>4</sub>.
-SOB medium is also available dry premixed from Difco, 0443-17.
+:*SOB medium is also available dry premixed from Difco, 0443-17.
+:*Adjust to pH 6.8-7.0 prior to use.  This requires approximately 25 ml of 1M NaOH per liter.
-Adjust to pH 6.8-7.0 prior to use.  This requires approximately 25 ml of 1M NaOH per liter.
+:*MgSO<sub>4</sub> should be autoclaved separately and added just before use.
-MgSO<sub>4</sub> should be autoclaved separately and added just before use.
 ==15/10 medium==