LB: Difference between revisions

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#10 g NaCl
#10 g NaCl


For plates also add
#15g agar
See also: [[Silver: LB Liquid]]
See also: [[Silver: LB Liquid]]


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Notes: We do not pH medium when we make it on the fly.  However, if it is really important, pH the medium to 7.0 with 5M NaOH (~200µL). Check with pH paper
Notes: We do not pH medium when we make it on the fly.  However, if it is really important, pH the medium to 7.0 with 5M NaOH (~200µL). Check with pH paper
===For plates===
#Mix dry ingredients and add distilled water up to less than 1 Liter
#After dissolved, add agar
#Pour into 2 L flask (or greater)
#Autoclave (liquid cycle)
#* 250°'''F''', 22psi, 30 minutes
#Cool media down to 60-55C (uncomfortable but not painful)
#Add appropriate antibiotic
#Pour the solution on sterile (???) plates
#Let solidify about 1 h, wrap, label (name, date, additive)
#keep at 4°C


==Source==
==Source==

Revision as of 14:23, 23 December 2011

Summary

Luria-Bertani Medium (aka L-Broth or LB Medium). (Bertani says LB really stands for lysogeny broth.) LB is a standard growth medium for a variety of bacteria and conditions.

Ingredients

  1. 10 g Bacto-tryptone
  2. 5 g yeast extract
  3. 10 g NaCl

For plates also add

  1. 15g agar

See also: Silver: LB Liquid

Note: There are two formulations of LB, Miller and Lennox, that differ in the amount of NaCl. Lennox has less salt, only 5 g/L. The Qiagen miniprep kit recommends LB with 10 g NaCl for highest plasmid yields.

Protocol

  1. Mix dry ingredients and add distilled water up to 1 Liter
  2. Pour into 2 L flask (or greater)
  3. Autoclave (liquid cycle)
    • 250°F, 22psi, 30 minutes

Notes: We do not pH medium when we make it on the fly. However, if it is really important, pH the medium to 7.0 with 5M NaOH (~200µL). Check with pH paper

For plates

  1. Mix dry ingredients and add distilled water up to less than 1 Liter
  2. After dissolved, add agar
  3. Pour into 2 L flask (or greater)
  4. Autoclave (liquid cycle)
    • 250°F, 22psi, 30 minutes
  5. Cool media down to 60-55C (uncomfortable but not painful)
  6. Add appropriate antibiotic
  7. Pour the solution on sterile (???) plates
  8. Let solidify about 1 h, wrap, label (name, date, additive)
  9. keep at 4°C

Source

Adapted From:

J. Sambrook, D.W. Russell, Molecular Cloning: A Laboratory Manual (Cold Spring Harbor Laboratory Press, New York, ed. 3, 2001) pg. A2.2