Exploring molecular interaction of cefpirome with human serum albumin: In vitro and in silico approaches

Abstract

Cefpirome (CFP), a fourth-generation cephalosporin for parenteral administration, is highly influential against gram-negative and gram-positive bacteria. Multiple approaches, such as fluorescence, absorption, voltammetric, and molecular docking were applied to assess the binding of CFP to the primary carrier protein, human serum albumin (HSA). The CFP-triggered quenching of HSA fluorescence reported the CFP−HSA complex formation, which was accomplished by a static quenching mechanism. A moderate binding affinity (Kf = 1.78 × 104 M−1 at 298 K) was found in the CFP−HSA interaction. The complex was anticipated to be stabilized by the presence of van der Waals interactions and hydrogen bonds. Upon CFP binding, microenvironmental alterations surrounding Trp and Tyr residues of HSA were observed. To establish the location of the CFP binding site in HSA, molecular docking studies were conducted, and the results indicated that CFP attaches to site I of HSA mostly through hydrophobic interactions and hydrogen bonding. The results of fluorescence spectroscopy and molecular docking supported one another quite well.