biostudies-literatureNi Dhufaigh KDepartment of Agriculture, Food and the Marine1258https://www.ebi.ac.uk/biostudies/studies/S-EPMC8226569biostudies-literatureUnknown9(6)Infection with the protozoan ectoparasite <i>Neoparamoeba perurans</i>, the causative agent of AGD, remains a global threat to salmonid farming. This study aimed to analyse the exoproteome of both an attenuated and virulent <i>N. perurans</i> isolate using proteomics and cytotoxicity testing. A disproportionate presence of proteins from the co-cultured microbiota of <i>N. perurans</i> was revealed on searching an amalgamated database of bacterial, <i>N. perurans</i> and Amoebozoa proteins. LC-MS/MS identified 33 differentially expressed proteins, the majority of which were upregulated in the attenuated exoproteome. Proteins of putative interest found in both exoproteomes were maltoporin, ferrichrome-iron receptor, and putative ferric enterobactin receptor. Protease activity remained signifMicroorganismsDifferential Exoproteome and Biochemical Characterisation of <i>Neoparamoeba perurans</i>.PMC8226569No. 15 S 745O'Connor IBotwright NDillon ESlattery OMacCarthy ENi Dhufaigh KfalseDifferential Exoproteome and Biochemical Characterisation of <i>Neoparamoeba perurans</i>.Infection with the protozoan ectoparasite <i>Neoparamoeba perurans</i>, the causative agent of AGD, remains a global threat to salmonid farming. This study aimed to analyse the exoproteome of both an attenuated and virulent <i>N. perurans</i> isolate using proteomics and cytotoxicity testing. A disproportionate presence of proteins from the co-cultured microbiota of <i>N. perurans</i> was revealed on searching an amalgamated database of bacterial, <i>N. perurans</i> and Amoebozoa proteins. LC-MS/MS identified 33 differentially expressed proteins, the majority of which were upregulated in the attenuated exoproteome. Proteins of putative interest found in both exoproteomes were maltoporin, ferrichrome-iron receptor, and putative ferric enterobactin receptor. Protease activity remained signif2021-01-01T00:00:00Z2021 Jun2026-05-05T03:07:32.867Z2022-02-10T19:52:15.137ZS-EPMC82265693420777610.3390/microorganisms9061258