Jack Preiss Research Interests continued
Various techniques and methodologies will be employed. They include the standard techniques of protein purification (including affinity chromatography), chemical modification (including photoaffinity labels), and isolation of peptides via HPLC. Recombinant DNA techniques are employed to clone the bacterial glycogen and starch biosynthetic enzymes in order to obtain levels so protein purification can be facilitated. Via DNA sequencing, we have deduced the amino acid sequences of the various enzymes.
The isolation of several mutants affected in the allosteric function of the E. coli ADPG pyrophosphorylase has been achieved and their genes have been cloned. By DNA sequencing, have determined the nature and location of the amino acid substitution. This has enabled us to do in vitro mutagenesis to further delineate structure and function of the effector sites. Using modern protein analyses and molecular modeling techniques we are attempting to study the various domains involved in allosteric function and catalysis. Another major effort is to crystallize the ADP glucose pyrophosphoylases, branching enzymes and glycogen synthase in order to obtain their three-dimensional structure.
Transfection of higher plants with the allosteric E. coli mutants has resulted in an increase of starch content in the plants and thus the study of these systems are also important on a commercial basis.
Full text of research interests