Eva Helmerhorst Assistant Professor helmer@bu.edu

education

MS, Vrije Universiteit, Amsterdam (The Netherlands); PhD, Academic Centre for Dentistry (ACTA), Amsterdam (The Netherlands)

research goals

Oral candidiasis is an infectious disease that affects immunocompromised patients. The disease is mainly caused by the fungus Candida albicans , which also resides as a harmless commensal in the oral cavities of approximately half of the healthy population. My research interest is in the role of saliva in maintaining the balance between Candida carriage and candidiasis. Our lab has extensive experience in studying the activity and mechanism of action of a variety of salivary antifungal proteins towards C. albicans and other pathogenic fungi. Some fungicidal proteins such as histatins have been found to be highly susceptible to proteolysis by enzymes that are associated with whole saliva. The activity of histatins and other proteins in the proteolytic context of whole saliva has become my major research interest and such studies will provide insight into the in vivo activity of these proteins in an oral environment.

representative publications

Helmerhorst EJ, Alagl AS, Siqueira WL, Oppenheim FG (2006). Oral fluid proteolytic effects on histatin 5 structure and function. Arch Oral Biol, in press.

Helmerhorst EJ, Venuleo C, Beri A, Oppenheim FG (2005). Candida glabrata is unusual with respect to its resistance to cationic antifungal proteins. Yeast 22: 705-14.

Mendelsohn RD, Helmerhorst EJ, Cipollo JF, Kukuruzinska MA (2005). A hypomorphic allele of the first N-glycosylation gene, ALG7, causes mitochondrial defects in yeast. Biochim Biophys Acta 1723:33-44.

Li J, Helmerhorst EJ, Leone CW, Troxler RF, Yaskell T, Haffajee AD, Socransky SS, Oppenheim FG ( 2004). Identification of early microbial colonizers in human dental biofilm. J Appl Microbiol 97:1311-8.

Helmerhorst EJ, Flora B, Troxler RF, Oppenheim FG ( 2004) Dialysis unmasks the fungicidal properties of glandular salivary secretions. Infect Immun 72:2703-9.

Li J, Helmerhorst EJ, Corley RB, Luus LE, Troxler RF, Oppenheim FG (2003). Characterization of the immunologic responses to human in vivo acquired enamel pellicle as a novel means to investigate its composition. Oral Microbiol Immunol 18:183-91.

Helmerhorst EJ, Murphy MP, Troxler RF, Oppenheim FG (2002). Characterization of the mitochondrial respiratory pathways in Candida albicans . Biochim Biophys Acta 1556: 73-80.

Helmerhorst EJ, Van 't Hof W, Breeuwer P, Veerman ECI, Abee T, Troxler RF, Nieuw Amerongen AV, Oppenheim FG (2001). Characterization of histatin 5 with respect to amphipathicity, hydrophobicity and effects on cell and mitochondrial membrane integrity excludes a candidacidal mechanism of pore formation. J Biol Chem 276: 5643-5649.

Gyurko C, Lendenmann U, Helmerhorst EJ, Troxler RF, Oppenheim FG (2001). Killing of Candida albicans by histatin 5: Cellular uptake and energy requirement. Antonie v. Leeuwenhoek 79: 297-309.

Gusman H, Travis J, Helmerhorst EJ, Troxler RF, Oppenheim FG (2001). Salivary histatin is an inhibitor of both host and bacterial enzymes implicated in periodontal disease. Infect Immun 69:1402-1408.

Helmerhorst EJ, Troxler RF, Oppenheim FG (2001). The human salivary peptide histatin 5 exerts its antifungal activity through the formation of reactive oxygen species. Proc Nat. Acad Sci USA 98: 14637-14642.

Flora B, Gusman H, Helmerhorst EJ, Troxler RF, Oppenheim FG (2001). A new method for the isolation of histatins from human parotid saliva using zinc precipitation. Prot Expres Purificat 23: 198-206.

Helmerhorst EJ, Hodgson R, Van 't Hof W, Veerman ECI, Allison C, Nieuw Amerongen AV (1999). The effects of histatin-derived antimicrobial peptides on oral biofilms. J Dent Res 78: 1245-1250.

Helmerhorst EJ, Breeuwer P, Van 't Hof W, Walgreen-Weterings E, Oomen LCJM, Veerman ECI, Nieuw Amerongen AV, Abee T (1999). The cellular target of histatin 5 on Candida albicans is the energized mitochondrion. J Biol Chem 274: 7286-7291.

Helmerhorst EJ, van 't Hof W, Simoons-Smit AM, Veerman ECI, Nieuw Amerongen AV (1997). Synthetic histatin analogs with broad spectrum antimicrobial activity. Biochem J 326: 39-45.

grant support

NIH/NIDCR Grant DE07652: Salivary Proteins in Dental Integuments. Role: Co-Investigator.

NIH/NIDCR Grant DE05672: Microbicidal Salivary Histidine-rich Proteins. Role: Co-Investigator.

NIH/NIDCR Grant DE14950: Salivary Diagnostics. Role: Co-Investigator