title: Ultrasensitive detection and characterization of posttranslational modifications using surface-enhanced Raman spectroscopy.
abstract: Posttranslational modification (PTM) of proteins is likely to be the most common mechanism of altering the expression of genetic information. It is essential to characterize PTMs to establish a complete understanding of the activities of proteins. Here, we present a sensitive detection method using surface-enhanced Raman spectroscopy (SERS) that can detect PTMs from as little as zeptomoles of peptide. We demonstrate, using model peptides, the ability of SERS to detect a variety of protein modifications, such as acetylation, trimethylation, phosphorylation, and ubiquitination. In addition, we show the capability to obtain positional information for modifications such as trimethylation and phosphorylation using SERS and wavelet decomposition data analysis techniques. We further show that it is possible to apply SERS to detect PTMs from biological samples such as histones. We envision that this detection method might be a valuable technique that is complementary to mass spectrometry in obtaining orthogonal chemical and modification-specific information from biological samples at sensitive levels.
authors.affiliation: Biomedical/Life Sciences, Digital Health Group, Intel Corporation, Santa Clara, California 95052, USA. narayan.sundararajan@intel.com
authors.forename: Narayan
authors.initials: N
authors.lastname: Sundararajan
authors.forename: Danqian
authors.initials: D
authors.lastname: Mao
authors.forename: Selena
authors.initials: S
authors.lastname: Chan
authors.forename: Tae-Woong
authors.initials: TW
authors.lastname: Koo
authors.forename: Xing
authors.initials: X
authors.lastname: Su
authors.forename: Lei
authors.initials: L
authors.lastname: Sun
authors.forename: Jingwu
authors.initials: J
authors.lastname: Zhang
authors.forename: Kung-bin
authors.initials: KB
authors.lastname: Sung
authors.forename: Mineo
authors.initials: M
authors.lastname: Yamakawa
authors.forename: Philip R
authors.initials: PR
authors.lastname: Gafken
authors.forename: Tim
authors.initials: T
authors.lastname: Randolph
authors.forename: Dale
authors.initials: D
authors.lastname: McLerran
authors.forename: Ziding
authors.initials: Z
authors.lastname: Feng
authors.forename: Andrew A
authors.initials: AA
authors.lastname: Berlin
authors.forename: Mark B
authors.initials: MB
authors.lastname: Roth
mesh_terms: D000107:Acetylation; D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D006657:Histones / Q000737:chemistry* / Q000378:metabolism*; D008745:Methylation; D010766:Phosphorylation; D011499:Protein Processing, Post-Translational; D012680:Sensitivity and Specificity; D013059:Spectrum Analysis, Raman / Q000379:methods*; D013499:Surface Properties; D013950:Thymus Gland / Q000737:chemistry / Q000378:metabolism
chemical_list: D006657:Histones