Assessing Cell Growth in a Microtiter Plate Reader with Selective Pressure Incorporation of Unnatural Selenium and Tellurium Containing Amino Acids

Abstract

Metalloid-containing unnatural amino acids, when incorporated into target proteins, provide a means of solving for three-dimensional structure by MAD or SAD techniques. The use of Tellurium-containing amino acids are of special interest since they can also be exploited by more traditional MIR techniques, which don’t require travel to synchrotron centers. Tellurium, when incorporated into protein as telluromethionine, generally induces toxicity to E. coli. Selenium, when incorporated as selenomethionine, induces much lower toxic effects to cell culture but remains problematic, at times. Altering growth conditions can potentially reduce such toxicity. This study demonstrates a rapid screening method for biosynthetic incorporation of unnatural amino acids by various forms of selective pressure.