Medium for cultivating microorganisms

Abstract

A medium for culturing microorganisms includes at least one compound which can be used as a source of phosphorus for microorganisms but which at least one compound will not precipitate Pb 2+ ions, so that the medium does not form a precipitate in the presence of up to about 25 mM Pb 2+ ions. Preferred compounds are O-phospho-L-amino acids. A buffer may be included in the medium. The medium is particularly well suited for remediating lead contaminated site by bioremediation.

What is claimed is:  
     
         1 . A medium for culturing microorganisms comprising at least one compound which can be used as a source of phosphorus for microorganisms but which at least one compound will not precipitate Pb 2+  ions, wherein said medium does not form a precipitate in the presence of up to about 25 mM Pb 2+  ions.  
     
     
         2 . The medium according to  claim 1  wherein the compound is an O-phospho-L-amino acid.  
     
     
         3 . The medium according to  claim 2  wherein the O-phospho-L-amino acid is O-phospho-L-threonine.  
     
     
         4 . The medium according to  claim 1  further comprising a buffer.  
     
     
         5 . The medium according to  claim 4  wherein the buffer is selected from the group consisting of buffers which include at least one sulfate group.  
     
     
         6 . The medium according to  claim 5  wherein the buffer is selected from the group consisting of Bis-Tris, BES, MOPS, ACES, and MOPSO.  
     
     
         7 . A method for remediating a lead contaminated site by bioremediation comprising contacting said site with a medium according to  claim 1 .  
     
     
         8 . A method for remediating a lead contaminated site by bioremediation comprising contacting said site with a medium according to  claim 2 .  
     
     
         9 . A method for remediating a lead contaminated site by bioremediation comprising contacting said site with a medium according to  claim 3 .  
     
     
         10 . A method for remediating a lead contaminated site by bioremediation comprising contacting said site with a medium according to  claim 4 .  
     
     
         11 . A method for remediating a lead contaminated site by bioremediation comprising contacting said site with a medium according to  claim 5 .  
     
     
         12 . A method for remediating a lead contaminated site by bioremediation comprising contacting said site with a medium according to  claim 6.