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bioRxiv · 10.1101/758920

Multi-epitope Peptide Vaccine Prediction for Candida albicans targeting Pyruvate Kinase Protein; an Immunoinformatics Approach

Abstract

The fungus Candida albicans is an opportunistic pathogen that causes a wide range of infections. Its the primary cause of candidiasis and the fourth most common cause of nosocomial infection. In addition, disseminated invasive candidiasis which is a major complication of the disease has an estimated mortality rate of 40%-60% even with the use of antifungal drugs. Over the last decades, several different anti-Candida vaccines have been suggested with different strategies for immunization against candidiasis such as, live-attenuated fungi, recombinant proteins, and glycoconjugates but none has been approved by the FDA, yet. This study aims to introduce a new possible vaccine for C. albicans through analyzing peptides of its pyruvate kinase (PK) protein as an immunogenic stimulant computationally.\n\nA total number of 28 C. albicans, pyruvate kinase proteins were obtained from NCBI on the 9th of February 2019 and were subjected to multiple sequence alignment using Bioedit for conservancy. The main analytical tool was IEDB, Chimera for homology modelling, and MOE for docking.\n\nAmong the tested peptides, fifteen promising T-cell peptides were predicted. Five peptides were more important than the others (HMIFASFIR, YRGVYPFIY, AVAAVSAAY, LRWAVSEAV, and IFASFIRTA) They show high Binding Affinity to MHC molecules, low binding energy required indicating more stable bonds, and their ideal length of nine peptides. (PTRAEVSDV) peptide is the most promising linear B-cell peptide due to its physiochemical parameters and optimal length (nine amino acids). Its highly recommended to have these five strong candidates in future in vivo and in vitro analysis studies.

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BibTeXRIS

sati, a. o. m., abdelmoneim, a. h., Dawoud, E., abbas, t., Abdelrahman, F., Saad, k., Abduallah, r., musrafa, m., Sidahmed, t., Elhassan, R., Hassan, M.. 2019-09-05. Multi-epitope Peptide Vaccine Prediction for Candida albicans targeting Pyruvate Kinase Protein; an Immunoinformatics Approach. https://doi.org/10.1101/758920

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