The Michel Research group was established in 2009. The Principal Investigator, Dr. Lea Vacca Michel, is an Associate Professor in the School of Chemistry and Materials Science. Dr. Michel is a biophysicist by training and currently works in the fields of protein biochemististry, structural biology, and immunology. Since 2009, the Michel Group has had over 30 research students (undergraduate and MS). Graduates from the Michel Group are enrolled in the world's best MD and PhD programs, such as Cornell University, Duke University, University of Toronto, and Yale University. Dr. Michel seeks to engage students from diverse backgrounds and has worked with many deaf and hard-of-hearing students in her research lab.
Lea Vacca Michel, Ph.D. is an Associate Professor in the School of Chemistry and Materials Science at the Rochester Institute of Technology. Currently, her work is focused on dual oriented bacterial lipoproteins and crystallin proteins, which are localized in the eye lens. Dr. Michel is the Chair of the Women in Science (WISe) program at RIT, Director of the Rochester Project SEED program, and Director of the Research Strand for the HHMI-funded Inclusive Excellence program at RIT. She strives to increase the participation of women and underrepresented minorities (including those who are deaf and hard-of-hearing) in science and math. Dr. Michel was recently featured in an article that appeared in Nature (Nature 558, 149-151 (2018)).
Nontypable Haemophilus influenzae (NTHi) causes acute otitis media, sinusitis, and acute exacerbations of chronic bronchitis. My interest in NTHi relates to its role in acute otitis media (ear infections) in children. Otitis media is the most common childhood illness for which pediatricians prescribe antibiotics [1-3] and current treatments and lost wages total $5 billion annually . The incidence and health care burden of ear infections in the United States points to the urgent need for a vaccine against NTHi.
The outer membrane lipoprotein P6, discovered almost 30 years ago, is currently one of the leading vaccine candidates for NTHi [5-7]. Although P6 has been studied for its immunological properties, not much was known about its structural orientation or localization in NTHi. It is critical for a vaccine candidate to be surface exposed in the bacterial cell such that it is accessible to antibodies and can initiate the appropriate immune response upon infection.
Our group has shown, using recombinant DNA technologies, recombinant protein expression/purification, enzyme-linked immunosorbent assays (ELISA), nuclear magnetic resonance (NMR) spectroscopy, and computational structural analysis, that P6 is not a transmembrane protein . However, past studies suggested that P6 interacted with the peptidoglycan layer inside of the cell [9-12] and monoclonal antibodies outside of the cell [12-16]. Thus, an apparent contradiction was presented. If P6 did not span the outer membrane, how could P6 interact with both intracellular and extracellular molecules? To address this apparent contradiction, I proposed the following hypotheses: P6 exists in two orientations in the outer membrane (see Figure): one in which P6 is facing out of the cell and one in which P6 is facing in towards the periplasm, P6 is not surface exposed,or P6 does not interact with peptidoglycan inside the cell.Only one other protein (Lpp of Escherichia coli) had been shown to exist in two forms, one form being surface exposed and the other internally localized within the cell . This was the only characterized example of a lipoprotein that was able to occupy two distinct subcellular locations and membrane orientations.
Our group showed that P6 was surface exposed in intact whole NTHi cells (using flow cytometry, a bactericidal assay, and confocal microscopy) and on the inside of NTHi (using Proteinase K digestion experiments). These experiments demonstrated that P6 was localized both inside and outside of NTHi (Figure 1A), pointing to a relatively novel biological phenomenon which we have called dual orientation. The results of this study were published in the Journal of Bacteriology in 2013 .
The goal of our next study was to determine whether or not P6’s homologue, Pal, in Escherichia coli (E. coli) was also dual oriented. Pal’s sequence and structure were highly similar to those of P6. Pal’s periplasmic binding partners have also been well established. Pal is one of the key components in the Tol-Pal complex interacting noncovalently with the peptidoglycan layer , outer membrane proteins OmpA  and Lpp , periplasmic protein TolB  and the inner membrane protein TolA . While its periplasmic interactions were well established, we considered the possibility that Pal might have a second orientation allowing for surface exposure (similar to P6). In this study, we utilized confocal microscopy, flow cytometry, and a biotinylation labeling technique to detect the surface exposed population of Pal. We discovered that Pal was also dual oriented, although the exposed population of Pal was smaller than the periplasmic population of Pal .
1. NIDCD: Health Info, Hearing, Ear, Infection and Deafness, Otitis Media (2002) NIH Pub No 97-4216.
2. Nyquist AC, et al (1998) JAMA 279: 875–877.
3. Berman S, et al (1997) Pediatrics 100: 585–592.
4. Gates GA (1996) Otolaryngol Head Neck Sur 114: 525-530.
5. Murphy TF, et al (1985) J Infect Dis 152: 1300-1307.
6. Murphy TF (2005) Expert Rev Vaccines 4: 843-853.
7. Murphy TF, et al (2005) Vaccine 23: 2696-2702.
8. Michel LV, et al (2011) Vaccine 29: 1624-1627.
9. Murphy TF, et al (1985) J Infect Dis 152: 1300-1307.
10. Chen R, et al (1987) Eur J Biochem 163: 73–77.
11. Deich RA, et al (1988) J Bacteriol 170: 489–498.
12. Bogdan JA, et al (1995) Infect Immun 63: 4395-4401.
13. Nelson MB, et al (1988) Rev Infect Dis 10: S331-S336.
14. DeMaria TF, et al (1996) Infect Immun 64: 5187-5192.
15. Green BA, et al (1987) Infect Immun 55: 2878-2883.
16. Kyd JM, et al (1995) Infect Immun 63: 2931-2940.
17. Cowles CE, et al (2011) Mol Microbiol 79: 1168-1181.
18. Michel LV, et al (2013) J Bacteriol 195: 3252-3259.
19. Leduc M, et al (1992) J Bacteriol 174: 7982-7988.
20. Clavel T, et al (1998) Mol. Microbiol 29: 359-367.
21. Cascales E, et al (2002) J. Bacteriol 184: 754-759.
22. Bouveret E, et al (1995) J Biol Chem 270: 11071-11077.
23. Cascales E, et al (2000) Mol Microbiol 38: 904-915.
24. Michel LV, et al (2015) Microbiology, in press.
The property that defines c-type heme proteins is the covalent attachment of the heme group to the polypeptide chain of the protein. The c-heme covalent attachment (usually by two Cysteine thioether linkages) is energetically expensive, and the biological motivation behind the attachment is still in question [25-28]. During my graduate work, I utilized NMR spectroscopy and other biochemical techniques to characterize the electronic and structural properties of cytochromes c (cyts c) from two different bacteria, with the goal of elucidating the biological role of the c-type heme in cyts c . I focused on the structural role of the c-type heme in modulating redox potential. Our current project assumes a far simpler but equally as captivating biological role for the c-type heme: to prevent the heme from being scavenged by pathogenic bacteria such as NTHi. A manuscript describing the results of our work on this project is in preparation.
25. Allen, JWA, et al (2005) Dalton T 21: 3410-3418.
26. Thony-Meyer L (2002) Biochem Soc Trans 30: 633-638.
27. Barker PD, et al (1999) Structure 7: R281-R290.
28. Thony-Meyer L (2000) Biochim Biophys Acta-Bioenerg 1459: 316-324.
29. Michel LV, et al (2007) Biochemistry 46: 11753-11760.
The eye lens contains a very high concentration of proteins, most of which are called crystallins . The crystallin proteins (α, β, and γ) are a diverse family of structural proteins whose main biological function is to control the refractive/reflective properties of the lens . In vivo, the α, β, and γ crystallins can interact with themselves and each other and can also aggregate into large clusters/chains [32-34]. These intermolecular interactions are thought to help control the amount of light scattering by the lens itself. As a person (or animal) ages, crystallins lose function and the proteins will aggregate to form an opaque "cloud" in the lens (cataract), thus reducing the amount of light able to enter the eye and severely decreasing vision .
The interactions between crystallin proteins have proven quite complex. For example, γ crystallins interact with each other and also play an important role in how the α-crystallins interact with each other. Even small structural changes (mutations) in the γ crystallins can have a significant effect on the "cloud" point of the γ crystallins, thus increasing one's susceptibility to cataracts . One of the major goals of our study (PI: George Thurston, RIT Physics) is to elucidate the specific interactions between bovine γ-B (homologous to human γ-D) crystallin proteins. We plan to map the specific interaction sites using NMR spectroscopy and probe changes in those interactions with changes in pH, protein concentration, and temperature.
30. Bhat SF (2003) Prog Drug Res 60: 205-262.
31. Jester JV (2008) Semin Cell Dev Biol 19: 82-93.
32. Thurston GM (2006) J Chem Phys 124: 134909.
33. Dorsaz N, et al (2009) J Phys Chem B 113: 1693-1709.
34. Dorsaz N, et al (2011) Soft Matter 7: 1763-1776.
35. Stradner A, et al (2007) Phys Rev Letters 99: 198103.
36. Banerjee PR, et al (2011) PNAS 108: 574-579.
One of our research projects is partially funded by the Camille and Henry Dreyfus Special Grant Program in the Chemical Sciences. The goal of the project is to better prepare deaf and hard of hearing (HOH) students for careers in the chemical sciences and increase their familiarity with the nature of graduate study. Unemployment rates for deaf/HOH people are non-proportionately high compared to rates for hearing people. In addition, only a handful of deaf/HOH students pursue graduate degrees in the sciences each year. I have been working with deaf/HOH students in my research group for several years, and as part of the Dreyfus study, I will continue to work with deaf/HOH students in the lab on independent research projects, formally assess the effectiveness of different mentoring techniques with those students, assess the effectiveness of technological communication devices, and expose RIT's deaf/HOH students to the opportunities that come with advanced degrees (i.e., graduate school).
Michel LV, Kaur R, Zavorin M*, Pryharski K, Khan MN, LaClair C*, O’Neil M*, Xu Q, Pichichero ME (2018) Intranasal coinfection model allows for assessment of protein vaccines against nontypeable Haemophilus influenzae in mice, Journal of Medical Microbiology 67: 1527-1532.
Sgheiza V*, Novick B*, Stanton S*, Pierce J*, Kalmeta B*, Holmquist MF*, Grimaldi K*, Bren KL, Michel LV (2017) Covalent bonding of heme to protein prevents heme capture by nontypeable Haemophilus influenzae, FEBS Open Bio 7: 1778-1783.
Gehret AU, Trussell JW, Michel LV (2017) Approaching Undergraduate Research with Students who are Deaf and Hard-of-Hearing, Journalof Science Education for Students with Disabilities 20 (1): Article 4.
Michel LV, *Shaw J, *MacPherson V, *Barnard D, *Bettinger J, *D’Arcy B, Surendran N, Hellman J, Pichichero ME (2015) Dual orientation of the outer membrane lipoprotein Pal in Escherichia coli, Microbiology 161: 1251-1259.
Michel LV, *Snyder J, *Schmidt R, *Milillo J, *Grimaldi K, *Kalmeta B, Khan N, Sharma S, Wright LK, Pichichero ME (2013) Dual orientation of the outer membrane lipoprotein P6 of nontypeable Haemophilus influenzae, J Bacteriology 195: 3252-3259.
Craig PA, Michel LV, Bateman RC (2013) A Survey of Educational Uses of Molecular Visualization Freeware, Biochemistry and Molecular Biology Education 41: 193-205.
Peterson JE, Zurakowski D, Italiano JE, Michel LV, Connors S, Oenick M, D’Amato RJ, Klement GL, Folkman MJ (2012) VEGF, PF4 and PDGF are elevated in platelets of colorectal cancer patients, Angiogenesis 15: 265-273.
Michel LV, *Kalmeta B, *McCreary M, *Snyder J, Craig P, Pichichero ME (2011) Vaccine candidate P6 of nontypable Haemophilus influenzae is not a transmembrane protein based on protein structural analysis, Vaccine 29: 1624-1627.
Chang A, Kaur R, Michel LV, Casey JR, Pichichero ME (2011) Haemophilus influenzae vaccine candidate outer membrane protein P6 is not conserved in all strains, Hum Vaccines 7: 102-105.
Peterson JE, Zurakowski D, Italiano JE, Michel LV, Fox L, Klement GL, Folkman J (2010) Normal ranges of angiogenesis regulatory proteins in human platelets, Am J Hematology 85: 487-493.
Michel LV, Bren KL (2008) Submolecular unfolding units of Pseudomonas aeruginosa cytochrome c551, J Biol Inorg Chem 13: 837-845.
Ye T, Kaur R, Senguin FT, Michel LV, Bren KL, Elliott SJ (2008) Methionine ligand lability of type I cytochromes c: Detection of ligand loss using protein film voltammetry, J Am Chem Soc. 130: 6682-6683.
Michel LV, Ye T, Bowman, SEJ, Levin BD, Hahn MA, Russell BS, Elliott SJ, Bren KL (2007) Heme attachment motif mobility tunes cytochrome c redox potential, Biochemistry 46: 11753-11760.
Parks B, Vacca L, Rumberger E, Hendrickson D, Christou G (2003) Effect of mechanical stress on the line width of single photon absorptions in Mn12-acetate, Physica B 329: 1181-1182.
Patent Pending: Michel LV, Hellman J (November 8, 2018) Diagnosing sepsis by detecting peptidoglycan associated lipoprotein (Pal) in urine (Application No. 62/757211).
Pichichero M, Khan MN, Kaur R, Sharma S, Casey J, Michel L (Accepted August 11, 2015) US Patent 9101568: Compositions and methods related to P6.
Personal donation to Rochester Project SEED (Director). June 2017 – August 2019 ($54,000).
HHMI Undergraduate Science Education – Inclusive Excellence Grants 2017(Co-PI). September 2017 – August 2022 ($1,000,000).
NIH R15. Phase Boundaries and Liquid Structure of Concentrated Eye Lens Protein Mixtures (Co-PI).September 2013 – August 2017 ($361,036).
The Camille and Henry Dreyfus Foundation: Special Grant Program in the Chemical Sciences. Quiet Chemistry: Working with Deaf Students in a Chemistry Research Laboratory (PI). September 2013 – December 2016 ($31,600).
RIT: NIH Grant Writing Bootcamp. Implicating Pal in Gram-Negative Sepsis (PI). May 1, 2018 – August 31, 2019 ($10,000).
RIT: FEAD grant. Probing the Pal-Peptidoglycan Interactions and their Role in Pal Release (PI). September 1, 2017 – March 31, 2018 ($5,500).
RIT: ADVANCE Connect Grants Program. Formal Evaluation of WISe (PI). May 2017 – March 2018 ($5,000).
RIT: Ronald D. Dodge Memorial Faculty Grant. Funding to support a student research assistant on the Dreyfus Quiet Chemistry project (PI). 2016-2017 ($1000).
RIT: ADVANCE Connect Grants Program. Crouching Tiger, Hidden Bias (PI). June 1, 2016 – May 31, 2017 ($1,950).
RIT: ADVANCE Connect Grants Program. WISe Distinguished Speaker Series (Co-PI). June 1, 2016 – May 31, 2018 ($6,800).
RIT: FEAD grant. Implicating Dual oriented Pal in Gram-negative sepsis (PI). July 1, 2015 – January 31, 2016 ($6,000).
RIT: ADVANCE Connect Grants Program. From WISe to WISE: Networking for Women in Science and Engineering (Co-PI). June 1, 2015 – May 31, 2016 ($8,100).
RIT: ADVANCE Connect Grants Program. WISe Networking and Leadership Initiatives (PI). June 2014 – December 2014 ($10,200).
RIT: Provost’s Faculty Mentoring Grant. Series of Women Faculty Lunches/Discussions (PI). January – December 2012 ($1900).
RIT: Dean’s Research Initiation Grant. Testing for Lipoprotein Dual Orientation in the Outer Membrane of Gram-Negative Bacteria (PI). May 2012 – April 2013 ($15,000).
RIT/RGH: SEED grant. Searching for an alternative vaccine candidate for nontypable Haemophilus influenzae (PI). February 2011 – January 2012 ($20,000).
RIT: Grant Writing Boot Camp. Evaluating P6 as one of the leading vaccine candidates for Nontypable Haemophilus influenzae (PI). March 2010 – February 2011 ($5,000).
1. Dr. Jennifer Milillo (2009-2011) (Medical School- SUNY Buffalo; Ped. Resident at Mt. Sinai Hospital, NYC; Critical Care Fellowship, Cohen Children’s Medical Center, NYC; Pediatric Intensive Care Doctor at Long Island Jewish Medical Center)
2. Nathaniel Huddleston (Summer 2010, Clinical Laboratory Science program, U of Illinois)
3. Arooj Iqbal (2010-2011) (MS program in Biomedical Science, New Jersey Medical School; Medical School- Lake Erie College of Medicine at Seton Hill)
4. Dr. Danielle Weekes (2010-2011) (Medical School-Meharry Medical College; Orthopedic Research at Rothman Institute)
5. Dr. Breanna Kalmeta (2009-2012) (Neuroscience PhD program- Duke University)
6. Dr. Kyle Grimaldi (2010-2012) (Med School- SUNY Buffalo; Emergency Med resident at UNC)
7. Dr. Anthony Mangan (2010-2012) (Biochemistry PhD program- U of Colorado Denver; HHMI Fellow; Postdoc at UNC Chapel Hill- IRACDA fellow)
8. Melody Frink (2011-2012) (Biochemistry PhD program- Ohio State University)
9. Dr. Joy Snyder (2009-2013) (PharmD program- St. John Fisher College; Wegmans Pharm residency)
10. Rachel Schmidt (2010-2013) (2 years of Physiology PhD program- Cornell University; Current- Lab technician III, U of Rochester)
11. Bethany Novick (2011-2014) (Chemistry MS Program- RIT)
12. John Bettinger (2011-2014) (Biochemistry PhD program- U of Rochester)
13. Victoria MacPherson (2013-2014) (Medical School- Philadelphia College of Osteopathic Med)
14. Valerie Sgheiza (2012-2015) (MA in Anthropology- California State U Chico; PhD in Anthropology- University of Illinois at Urbana-Champaign)