Originally from the small town of Sligo on the northwest coast of Ireland, Dr. Carroll received his undergraduate degree in Microbiology from Trinity College Dublin (Ireland) in 1999 and the same year began his Ph.D. research in the laboratory of Prof. Charles Dorman. For his Ph.D. Carroll studied the regulation of virulence gene expression by nucleoid-associated proteins in Salmonella typhimurium.
Carroll moved to the United States in 2004 to begin a postdoc at the University of Illinois at Chicago, where he continued to study gene regulation in S. typhimurium, focusing on bacterial two component signal transduction systems. In 2008 he moved to Houston, Texas, to begin a postdoc position at The Methodist Hospital Research Institute (TMHRI). The focus of his research at TMHRI was genomic and transcriptomic analyses of the Gram-positive pathogen Streptococcus pyogenes.
He left Houston in 2010 and later that year moved to Tampa, Fla., to begin working at the University of South Florida in the laboratory of Dr. Lindsey Shaw. At USF he studied the role of exopeptidases in Staphylococcus aureus and conducted a variety of genomic, transcriptomic and metagenomic projects using next-generation DNA sequencing. In 2014 he accepted a faculty position in the Department of Biological Sciences at Ohio University. In addition to teaching Microbiology, Carroll has a research group that studies the mechanisms that S. aureus and MRSA uses to cause disease in humans.