Hello Corbin, 

have to tried increasing the solubility of protein by using  L-Aspartic Acid and L-Arginine in re-suspension and purification buffer rather than in LB media. You can try this using reference as mentioned in http://pubs.acs.org/doi/pdf/10.1021/ja049297h

Hi tere,

The easier is to prepare filtered sterile stock solutions as for yeast media  supplements (usually solutions are x100 up to x1000 dependng on solubility and and the final concentration is LB). pH should be adjusted as LB is not actually buffered.

Hi Corbin, 

I only have experience of adding amino acids to yeast media, but for this I made stock solutions first, sterile filtered them and then added the relevant volume of these to the liquid medium to get my desired concentration of each amino acid. After that, I autoclaved the medium and stored it at room temperature out of direct sunlight ready to use. I didn't bother to alter the pH of the amino acid stocks or media and I didn't have any issues using this method. 

Best of luck! 

Jonathan

Hello Corbin, 

have to tried increasing the solubility of protein by using  L-Aspartic Acid and L-Arginine in re-suspension and purification buffer rather than in LB media. You can try this using reference as mentioned in http://pubs.acs.org/doi/pdf/10.1021/ja049297h

I agree with the comments above. You have to filter your amino acid stock solution under aseptic condition and add the desired volume to a sterile LB media inside a laminar hood. You can also refer the paper on the effect of chemical  chaperones for improving expression of soluble proteins. Here is the link. I hope it helps. Good luck!

http://aem.asm.org/content/77/13/4603.full

Thank you all for the advice! I will start with a filter sterilized stock and see how that works.

Corbin

Protocols on amino-acid stocks:

1) from the famous Studier's paper on protein expression in E .coli (https://www.ncbi.nlm.nih.gov/pubmed/15915565) (especially, Table 1): http://www.sciencedirect.com/science/article/pii/S1046592805000264?via%3Dihub#tbl1

2) from the famous paper on synthetic Drosophila food medium (https://www.ncbi.nlm.nih.gov/pubmed/24240321) : especially, Supplementary Table 1.