The ability of the Aspergillus flavus to adapt within host environment is crucial for its colonization. Other than Aspergillus fumigatus, inhalation of A. flavus conidiaresulted in second most leading cause of aspergillosis. Onset of germination of conidia is one of the crucial events, thus in order to gain insight of the A. flavus adaptation while germinating, intracellular cellular protein profile of A. flavus MTCC9367 was obtained.
About more than 90% of conidia showed germination after 7h of incubation at 30°C in Sabouraud dextrose broth. Thus, samples were collected at this time-point for protein extracted from two biological samples. Protein profiling was performed in triplicate from the protein sample on a nanoflow LC Q-TOF mass spectrometer. The spectral data from MS scan from A. flavus MTCC9367 protein sample were search using Protein Lynx Global Server (PLGS 2.2.5) software against the A. flavus and Aspergillus species of UniProt databases.
A total 412 proteins were identified from different Aspergillus species databases, out of which 152 proteins were from A. flavus. Orthologs of A. flavus proteins were observed in A. fumigatus, A. parasiticus, A. niger, A .terreus, A. clavatus etc. Number of proteins in our analysis showed match with proteins sequence from other Aspergillus species but not to A. flavus protein sequence available at Uniprot database. Functional categorization of proteins resulted majorly to cell wall biogenesis/organization, carbohydrate and amino acid metabolism, energy, transcription, protein synthesis and degradation. Proteins/enzymes associated with secondary metabolite production, aflatoxin biosynthesis were also observed. We also observed Dicer-like protein 1 & 2 involved in post-transcriptional regulation. Proteins involved in cell signaling such as serine threonine protein kinases (e.g., nek1, nek2, nek3, ste20, MARK2, atg1, ssn3, cbk1) & serine threonine protein phosphatase were also observed.
Overall the data presents the catalogue of proteins/enzymes, transcriptional regulator or activator involved in germination of A. flavus conidia and could be applied to other Aspergillus species.