Eva Helmerhorst Associate Professor helmer@bu.edu

education

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

research interests

Saliva is well known to play a major role in maintaining oral health conditions by interfering with the adverse affects of oral pathogens. My research interests focus on the structure-function relationships of salivary proteins. Most important in this host protection by saliva is the capacity of several salivary proteins to protect oral hard and soft tissues. More recent studies with pure salivary proteins isolated from sterile glandular secretions have shown that functional domains representing short segments of the native proteins also exhibit antimicrobial and mineral homeostasis characteristics. Once these native proteins derived from the glandular secretions enter the oral cavity they are exposed to a host of enzymes including proteases. My projects are specifically geared towards an understanding of the proteolytic fragmentation of these glandular proteins using proteomics approaches for their structural characterization and specific bioassays to evaluate the effects of proteolysis on the functional spectrum of these salivary macromolecules.

representative publications

Campese M, Sun X, Bosch JA, Oppenheim FG, Helmerhorst EJ. Concentration and fate of histatins and acidic proline-rich proteins in the oral environment. Arch Oral Biol. 2009. In press.

Helmerhorst EJ, Sun X, Salih E, Oppenheim FG. Identification of Lys-Pro-Gln as a novel cleavage site specificity of saliva-associated proteases. J Biol Chem. 2008. 283:19957-66.

Helmerhorst EJ, Oppenheim FG. Saliva: a dynamic proteome. J Dent Res. 2007. 86: 680-693.

Walt DR, Blicharz TM, Hayman RB, Rissin DM, Bowden M, Siqueira WL, Helmerhorst EJ, Grand-Pierre N, Oppenheim FG, Bhatia JS, Little FF, Brody JS. Microsensor arrays for saliva diagnostics. Annals NY Acad Sci. 2007. 1098: 389-400.

Oppenheim FG, Salih E, Siqueira WL, Zhang W, Helmerhorst EJ. The salivary proteome and its genetic polymorphisms. Annals NY Acad Sci. 2007. 1098: 22-50.

Helmerhorst EJ. Whole saliva proteolysis: a wealth of information for diagnostic exploitation. Annals NY Acad Sci. 2007. 1098: 454-460.

Helmerhorst EJ, Alagl AS, Siqueira WL, Oppenheim FG. Oral fluid proteolytic effects on histatin 5 structure and function. Arch Oral Biol. 2006. 51: 1061-1070.

Helmerhorst EJ, Venuleo C, Beri A and Oppenheim FG. Candida glabrata is unusual with respect to its resistance to cationic antifungal proteins. Yeast 2005. 22:705-714.

Helmerhorst EJ, Stan M, Murphy MP, Sherman F and Oppenheim FG. The concomitant expression and availability of conventional and alternative, cyanide-insensitive, respiratory pathways in Candida albicans. Mitochondrion 2005. 5: 200-211.

Li J, Helmerhorst EJ, Leone CW, Troxler RF, Yaskell T, Haffajee AD, Socransky SS and Oppenheim FG. Identification of early microbial colonizers in human dental biofilm. J Appl Microbiol 2004. 97:1311-18.  

Li J, Helmerhorst EJ, Troxler RF and Oppenheim FG. Identification of in vivo pellicle constituents by analysis of serum immune responses. J Dent Res 2004. 83:60-64.

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

Helmerhorst EJ, Troxler RF and Oppenheim FG. The human salivary peptide histatin 5 exerts its antifungal activity through the formation of reactive oxygen species. Proc Nat Acad Sci USA 2001. 98:14637-42.

Gusman H, Travis J, Helmerhorst EJ, Troxler RF and Oppenheim FG. Salivary histatin is an inhibitor of both host and bacterial enzymes implicated in periodontal disease. Infect Immun 2001. 69:1402-08.

Helmerhorst EJ, Van 't Hof W, Breeuwer P, Veerman EI, Abee T, Troxler RF, Nieuw Amerongen AV and Oppenheim FG. 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 2001. 276:5643-5649.

Helmerhorst EJ, Breeuwer P, Van 't Hof W, Walgreen-Weterings E, Oomen LCJM, Veerman ECI, Nieuw Amerongen AV and Abee T. The cellular target of histatin 5 on Candida albicans is the energized mitochondrion. J Biol Chem 1999. 274:7286-91.

Helmerhorst EJ, Reijnders IM, Van 't Hof W, Simoons-Smit AM, Veerman EI and Nieuw Amerongen AV. Amphotericin B and fluconazole-resistant Candi­da spp., Aspergillus fumigatus, and other newly emerging pathogenic fungi are susceptible to basic antifungal peptides. Antimicrob Agents Chemother 1999. 43:702-704.

Helmerhorst EJ, Hodgson R, Van 't Hof W, Veerman EI, Allison C and Nieuw Amerongen AV. The effect of histatin-derived antimicrobial peptides on oral bio­films. J Dent Res 1999. 78:1245-50.

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

grant support

NIH/NIDCR Grant DE18132 (R21): Oral Fluid Proteolytic Effects on Salivary Protein Structure and Function. Role: Principal Investigator.

NIH/NIDCR Grant DE16699 (R03): Oral Yeast Carriage and Salivary Antifungal Activity. Role: Principal Investigator.

NIH/NIDCR Grant DE07652 (R01): Microbicidal Salivary Histidine-rich Proteins. Role: Co-Investigator.

NIH/NIDCR Grant DE05672 (R01): Salivary Proteins in Dental Integuments. Role: Co-Investigator.

NIH/NIDCR Grant DE17788 (U01): Microsensor Arrays for Salivary Diagnostics. Role: Co-Investigator.

NIH/NIDCR Grant DE018448 (R21): Phosphoproteomics of Oral Fluids. Role: Co-Investigator.