Comparative Analysis of in-Vitro Susceptibility of Filamentous Fungal Isolates to Cell Penetrating Peptide–Conjugated Natamycin Versus Natamycin Alone
To compare the minimum inhibitory concentration (MIC) of filamentous fungal isolates to novel cell penetrating peptide conjugated natamycin with natamycin alone.
A novel cell penetrating peptide (CPP) conjugated natamycin was synthesized by conjugating two molecules of the CPP, tat, with natamycin to create tat2-nat. In vitro susceptibility of filamentous fungal isolates to tat2-nat and natamycin was evaluated according to Clinical and Laboratory Standards Institute (CLSI) methods. MIC of the various isolates was determined and compared. Mutated tat conjugated natamycin (mtat2-nat) was used as control.
Six isolates evaluated in the study include two ocular isolates, one each of Fusarium solani and Aspergillus niger and three non ocular isolates, one each of Aspergillus niger, Paecilimyeces spp. and Scedosporium spp. and MTCC stain of Fusarium solani (IMTECH, Chandigarh, India).Comparable MIC values were noted between Natamycin alone and the Conjugate.Tat2 alone also showed low MIC value of 0.25 against ocular isolate of Fusarium solani as compared to 16 with natamycin alone.
Cell penetrating peptides seem to have a potential role to play as antifungal agents, alone as well as in a conjugated form with natamycin. Further studies exploring their role in-vivo are warranted.