My research focuses on the molecular analysis of virulence in oral microorganisms, specifically the periodontal pathogenic bacterium Porphyromonas gingivalis and the fungal pathogen Candida albicans. Our research involves a combination of molecular genetics, genomics and transcriptomics. We also carry out 16s profiling of the oral microbiome to better understand oral disease. Our research is carried out in the Microbiology laboratory at the Dublin Dental University Hospital, which is on the campus of Trinity College Dublin.
Selected Recent Publications:
Sullivan DJ, Berman J, Myers LC, Moran GP. Telomeric ORFS in Candida albicans: does Mediator tail was the yeast? PloS Pathogens, 2015, 11(2): e1004614. Pubmed
Haran J, Boyle H, Hokamp K, Yeomans T, Liu Z, Church M, Fleming AB, Anderson MZ, Berman J, Myers LC, Sullivan DJ, Moran GP, Telomeric ORFs (TLOs) in Candida spp. encode Mediator subunits that regulate distinct virulence traits, PLoS Genetics, 10, (10), 2014, pe1004658- Pubmed
Miajlovic H, Cooke NM, Moran GP, Rogers TR, Smith SG. The response of Extra-Interstinal Pathogenic Escherichia coli to human serem reveals a protective role for Rcs-regulated exopolysaccharide colanic acid. Infection and Immunity, 2014; 82 (1): 298-305. PubmedMcGinley EL, Dowling AH, Moran GP, Fleming GJ, Influence of S. mutans on Base-metal Dental Casting Alloy Toxicity. Journal of Dental Research, 2013; 92 (1): 92-97. Pubmed
Moran GP. Transcript profiling reveals rewiring of iron assimilation gene expression in Candida albicans and C. dubliniensis. FEMS Yeast Research, 2012; 12:918-923. Pubmed
Higgins J, Pinjon E, Oltean HN, White TC, Kelly SL, Martel CM, Sullivan DJ, Coleman DC and Moran GP. Triclosan antagonises fluconazole activity against Candida albicans. Journal of Dental Research, 2012; 91(1): 65-70. Pubmed
Moran GP, Coleman DC and Sullivan DJ. Comparative Genomics
and The Evolution of Pathogenicity in Human Pathogenic Fungi. Eukaryotic Cell. 2011; 10:34-42. PubMed
R. Martin, GP Moran, I. D. Jacobsen, A. Heyken, J. Domey, D. J. Sullivan, O. Kurzai, B. Hube, The Candida albicans-Specific Gene EED1 Encodes a Key Regulator of Hyphal Extension, PLoS One, 6, (4), 2011, pe18394. PubMed
O'Connor, L, Caplice N, Coleman DC, Sullivan DJ, and Moran GP. Differential filamentation of Candida albicans and C. dubliniensis is governed by nutrient regulation of UME6 expression. Eukaryotic Cell. 2010; 9: 1383-1397. Pubmed
Virulence in Oral Candida species:
Candida albicans is a common resident in the oral cavity but can cause both superficial and serious bloodstream infections in immunocompromised hosts. We use molecular biology and genomic approaches to understand the pathogenesis of candidal infections with the overriding goal of identifying new therapeutic approaches to candidiasis.
The role of the telomeric TLO genes in virulence of C. albicans. Together with Prof Derek Sullivan at the DDUH, we are investigating the role of this novel telomeric gene family encoding orthologues of the Med2 protein, a component of Mediator complex. We are interested in why C. albicans has evolved to possess such a large number of TLO orthologues (~14 copies) and how expression of these proteins could afford phenotypic diversity on the organism
Funded by: Science foundation Ireland
PhD Student: John Haran
The role of Tor1 kinase in growth and virulence in C. albicans.
We are investigating the role of this essential eukaryotic kinase in growth and virulence of C. albicans. Tor has been implicated in the control of adhesin gene expression and filamentous growth in this fungal pathogen.
Funded by: Science Foundation Ireland
PhD Student: Peter Flanagan
Virulence in Porphyromonas gingivalis:
P. gingivalis is intimately linked with the development of severe periodontal disease, the major cause of tooth loss in adults. It is an anaerobic bacterium, and together with other anaerobic microbes such as Tanerella forsythia and Treponema denticola, it forms a subgingival biofilm capable of persisting and initiating a chronic inflammatory reaction that can destroy the tissues and bone supporting the tooth.
Analysis of the HagB and HagC genes of P. gingivalis in virulence and host response. HagB and HagC encode cell surface proteins with vaccine potential that are proposed to play a role in adhesion in P. gingivalis. Their exact role is poorly characterised and this project will generate a double HagB/C mutant to assess their role in the virulence and immune evasion of P. gingivalis.
Funded by: Trinity College Dublin 1252 Studentship and the Dublin Dental University Hospital
PhD Student: Eimear Connolly
Analysis of the Oral Microbiome:
This is a pilot study to analyse the microbiome of oral lesions with malignant potential in order to identify microbial changes that may be associated with malignancy. These microbial signatures could shed light on the etiology of these lesions and could be used to predict malignant transformation. In collaboration with the Sequencing Centre at St James’s hospital, we will use Illumina DNA sequencing to generate 16s rRNA profiles of the human oral micro biome.
PhD Student: Abdrazak Ben Amer (Libyan Govt. Scholar)