Yanan Qin

Yanan QinBrandeis / Biology, Computer Science
Hosted by Xu's Lab

“Nucleopeptide Assemblies to Differentiate ATP and ADP in Complex Medium”

Yanan Qin, Huaimin Wang, Bing Xu

Abstract

Adenosine triphosphate (ATP), one of the biological anions, plays crucial roles in several biological processes including energy transduction, cellular respiration, enzyme catalysis and signaling. Therefore, selective detection of these polyphosphate species under biological conditions would help elucidate their roles and related physiological events. In this project, we report the design of nucelopeptide which can selectively differentiate ATP rather than ADP and AMP in complex medium (even in human serum). Introducing nucleoside as a capping group for peptides is the prerequisite condition for the selectively recognition.

Prototype Thy-FFKKFKLKL (pep-8) was determined by comparing it with Nap-FFKKFKLKL and AC-FFKKFKLKL. Then seven nucleopeptides were derived from the prototype. The nucleopeptides were synthesized by solid phase polypeptide synthesis then purified by performing High-Performance Liquid Chromatography (HPLC). Then they were treated in PBS buffer with 1 equiv. of ATP or ADP. Transmission Electron Microscopy (TEM) images were taken for testing. Stereochemistry and arrangement of the mixture of ATP/nucleopeptide were investigated. Pep-8 with D configuration (D-8) was tested in ATP/ADP oscillation.

We have confirmed that the nucleopeptide assemblies were able to recognize ATP rather than ADP by forming precipitates or hydrogel. The sequences of nucleopeptides are important. Our design for nucleopeptides with Dconfiguration still has function in ADP/ATP oscillation. In the future, ATP recognition by the eight nucleopeptides will be tested in drug-resistant cells with 1 equiv. of ATP and ADP.

Support: SMURF (Summer MRSEC Undergrad Research Fellowship)