Ming Hansen-Gong

Ming Hansen-Gong taylorgong3616@gmail.com

(626) 759-2211

212 E. 12TH

St.

Imperial, NE 69033

Career Objective To obtain a position as a chemist where I can develop my skills and

experience.

Experience California State University, Los Angeles Graduate Assistant, 2011 - 2014

· Conducted experiments on Atomic Absorption Spectrometer,

Florescence, Surface Plasmon Resonance, High Performance

Liquid Chromatography, Mass Spectrometer, UV-visible, pH meter,

Inductively Coupled Plasma Mass Spectrometry, Gas Chromatography

· Supplied students with extra knowledge about subjects being studied

· In charge of making presentation videos and writing lab manuals

· Graded homework and lab reports

California State University, Los Angeles Research Professional, 2011 – 2014

· Conduct research projects on daily basis using various instruments

· Planned and organized lab tours for visiting scholars

· In charge of creating and filing paperwork

· Organized lab meetings

· Trained new students on lab instruments and procedures

· Maintained lab instruments

Education Masters of Science in Chemistry, California State University, Los Angeles, 2014

http://www.calstatela.edu/

Bachelors of Science in Chemistry Liaoning Shihua University, 2010

http://www.lnpu.edu.cn/english/general/index.htm

Dr. Zhou Recommendation:

Dr. Zhou was my Personal Instructor from fall of 2012 to summer 2014 at California

State University, Los Angeles. He informed me to let hiring companies contact him in

regards to my recommendation.

Dr. Feimeng Zhou Professor of Chemical and Biochemical Department California State University, Los Angeles (323) 343-2300 fzhou@exchange.calstatela.edu

Kinetic Studies of Amyloidogenic Hexapeptides as β-Amyloid (Aβ) Peptide

Inhibitors

Graduate Prospectus by

Ming Gong

Abstract

Aggregation of β-amyloid (Aβ) peptides has been linked to the pathology of

Alzheimer’s disease (AD). Inhibition or reversal of the Aβ peptide aggregation is a

promising therapeutic approach for treating AD. Short peptides that are capable of

breaking stacked β-sheets have been shown to inhibit Aβ aggregation. In this work, we

will use surface plasmon resonance (SPR) to study the kinetics of the breakage of Aβ

aggregates by hexapeptides of different properties.

Objectives

The aim of this study is to (1) develop SPR as a label-free and facile method to

screen short peptides that can effectively dissociate Aβ aggregates, and (2) correlate the

physical properties (e.g., hydrophobicity and hydrogen bonding) to the inhibitory efficacy.

Background

Dementia in the elderly is very common, additionally it has been reported that 60

to 70% of dementia is caused by Alzheimer’s disease (AD). AD is a progressive

neurodegenerative disorder that gradually affects the patient’s cognitive functions and

eventually causes death. The total prevalence of AD in the United States is estimated at

5.4 million, where 5.2 million cases are documented in people of the age 65 and older.1

Although the cause of AD remains undiscovered, increasing evidence have shown that

misfolding of Aβ could be the potential cause.2

Amyloid β(1-42) (Aβ42) is a single 42-redisue peptide created by the cleavage of

amyloid precursor protein (APP). It can aggregate into insoluble amyloid plaques in the

human brain.3The generally accepted process for Aβ42 aggregation is the conformational

transition from the natively unstructured form to β-sheet-rich oligomeric form and

subsequent reorganization to form cross-β-sheet fibrils.4-5

A potential therapeutic

modality to treat AD is to use inhibitors to prevent Aβ misfolding and aggregation.6-9

A strategy used to combat the aggregation of Aβ is to design inhibitors that work

by interfering with the formation of Aβ oligomers, or the clearance of Aβ oligomers.10-12

Various compounds are created as highly potential and clinical agents, such as peptide

mimetics,13

polymers,14

and small organic compounds.15

Among them, peptide-based

inhibitors are more promising compounds, because they are biocompatible and easy to

synthesis.

A collaborator of ours, using computational chemistry, has shown that using

hexapeptides, which we will refer to as amyloidogenic hexapeptides can prevent

aggregation of Aβ. The hypothesis is that these small peptides will bind with the

hydrophobic Aβ C-terminus and prevent it from aggregating into amyloid plaques.

Typical biochemistry methods of identifying the interactions between Aβ and these

hexapeptides cannot provide real time kinetics results at low concentrations. To

overcome this problem, SPR is employed to investigate the binding affinities between Aβ

and hexapeptides. We are hoping to find a therapeutic modality to treat AD.

Materials and Methods SPR is a powerful optical technique for studying bimolecular interactions due to

its high sensitivity and label free detection.16

SPR occurs when the polarized light hit

backside of a gold-coated sensor chip through a prism. At the resonance angle, light is

absorbed by the electrons onto the gold film, which causes a change in the beam’s

reflection known as SPR dip. The shape and location of the SPR dip can then be used to

convey information binding or unbinding of molecules or proteins attached to the gold

surface.17

In this project, by monitoring this shift vs. time, we will study the binding

affinities between Aβ and hexapeptides to verify if computational designed hexapeptides

can practically prevent Aβ aggregation.

In particular, we will use SPR to perform the kinetic study between Aβ42 and

hexapeptides. The experiments we propose are to:

Obtain a homogeneous solution of monometric Aβ42

Aβ42 is purified by following thr basic purification step to obtain a

homogeneous solution of monomeric Aβ42 in unstructured conformation. Briefly,

Aβ42 is dissolved in 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP, 99.9%) for two h

(1mg/ml), sonicated for 30 min to remove any preexisting aggregates or seeds,

and Centrifuged at 4 C at 14000 rpm for 30 min. 75% of the supernatant is

subpacked and frozen with liquild nitrogen and then dried with a freeze dryer. The

try Aβ42 powder is lyophilized at -80C and then stored in -20C fridge for use.

Immobilize monometric Aβ onto self-assembled streptavidin (SA) sensor chip

surface

Obtain a homogeneous solution of monometric hexapeptides

List of hexapeptides: VYIMIG

ITLFWG

CTLFWG

VTLWWG

GTVWWG

GILFWG

Determine the binding affinities between designed peptides and Aβ42.

Significance

The major significance of this research is to develop biocompatible peptide-based

inhibitors for Aβ aggregation. The computational design and experimental verification of

hexapeptides could possibly provide a new approach of treatment for over 5.4 million AD

patients. Moreover, if this method proves to be viable, it could be applied to other

neurodegenerative disorders caused by self-aggregation proteins.

Reference

(1) Hebert, L. E.; Scherr, P. A.; Bienias, J. L.; Bennett, D. A.; Evans, D. A. Archives of

Neurology, 2003, 60, 1119–22.

(2) Wang, Q.; Shah, N.; Zhao, J.; Wang, C.; Zhao, C.; Liu, L.; Li, L., Zhou, F.; Zheng, J.

Phys. Chem. Chem. Phys., 2011, 13, 15200-15210.

(3) Hardy, J.; Selkoe, D. J. Science, 2002, 297, 353–356.

(4) Ding, F.; Borreguero, J. M.; Buldyrey S. V.; Stanley H. E.; Dokholyan N. V. Proteins,

2003, 53, 220–228.

(5) Yanagisawa, K. Biochem Subcell. 2005, 38, 179–202.

(6) Yamin, G.; Ruchala P.; Teplow, D. B. Biochemistry 2009, 48, 11329-11331.

(7) Soto, P.; Griffin, M. A.; Shea, J. E. Biophys. J. 2007, 93, 3015-3025.

(8) Takahashi, T.; Mihara, H. Acc Chem Res, 2008, 41, 1309-1318.

(9) Hamaguchi, T.; Ono, K.; Yamada, M. Cell Mol Life Sci, 2006, 63, 1538-1552.

(10) Dash, P. K.; Moore, A. N.; Orsi, S. A. Biochem. Biophys. Res. Commun. 2005, 338,

777-782.

(11) Asai, M.; Hattori, C.; Iwata, N.; Saido, T. C.; Sasaqawa, N.; Szabó, B.; Hashimoto,

Y.; Maruyama, K.; Tanuma, S.; Kiso, Y.; Ishiura, S. J. Neurochemistry, 2006, 96, 533-

540.

(12) Bacskai, B. J.;, Kajdasz, S. T.; Christie, R. H.; Carter, C.; Games, D.; Seubert, P.;

Schenk, D.; Hyman, B. T. Nat. Med., 2001, 7, 369-372.

(13) Cleary, J. P.; Walsh, D. M.; Hofmeister, J. J.; Shankar, G. M.; Kuskowski, M. A.;

Selkoe, D. J.; Ashe, K. H. Nat Neurosci, 2004, 8, 79-84.

(14) Cabaleiro-Lago, C.; Quinlan-Pluck, F.; Lynch, I.; Lindman, S.; Minoque, A. M.;

Thulin, E.; Walsh, D.M.; Dawson, K. D.; Linse, S. J Am Chem Soc, 2008, 130, 15437-

15443.

(15) Jameson, L. P.; Smith, N. W.; Dzyuba, S. V. ACS Chemical Neuroscience, 2012, 3,

807-819.

(16) Myszka, D. G. Curr. Opin. Biotechnol, 1997, 8, 50-57.

(17) Skoog, D. A.; Holler, F. J.; Nieman, T. A. Principles of Instrumental Analysis;

Messina, F.; 5th

ed; Saunders College: Orlando, FL, 1998.