Journal of Chromatography & Separation Techniques
Open Access

Chemical modification of peptides followed by mass spectrometry: Implications in proteomics

2^nd International Conference on Current Trends in Mass Spectrometry

July 20-22, 2016 Chicago, USA

Medicharla V Jagannadham

CSIR-Centre for Cellular and Molecular Biology, India

Scientific Tracks Abstracts: J Chromatogr Sep Tech

Abstract :

Determination of the sequence of the peptides, obtained from the proteolysis digestion of a protein, using mass spectrometry, is a crucial requirement in proteomics. Sequence of the tryptic peptides is usually obtained by database search or by de novo sequencing. The poor spectral quality and signal to noise ratio interferes in the analysis. Different types of algorithms (MASCOT, SEQUEST and others) are used for interpretation of the mass spectral data. When the database is not available, de novo sequencing is the only way to determine the sequence. The de novo sequence can be obtained by employing different methods of fragmentation (CID, HCD, ETD and ECD), getting information on their sequence and combining this information. Even with MS instruments with high mass accuracy and speed of analysis, the reproducibility of the mass spectrometry-based proteomics is being questioned from time to time. Acetylation of peptides improved the spectral quality, exhibited by an increase in b ion intensities in the MS/MS spectra, improves the efficiency of de novo sequence and helped in validating the database search results. It is a simple reaction, which can be carried out on complex protein digests as is required in proteomics. The identification of proteins from an Antarctic bacterium Pseudomonas syringae Lz4W and other species using this strategy will be discussed.

Biography :

Medicharla V Jagannadham is working as a senior principal scientist and project leader at the Centre for Cellular and Molecular Biology. He published 45 research papers in internationally reputed scientific journals. He trained several students, conducted meetings and workshops in proteomics. He received “Bharat Jyothi” award from India International Friendship Society, New Delhi in 2014 and “Eminent Mass Spectrometrist” award from the Indian Society for Mass spectrometry (ISMAS) in 2015. His current research Interests are proteomics, particularly in improving the de novo sequencing efficiency of peptides using MS techniques, structural and functional studied of outer membrane vesicles of Gram-negative bacteria.

Email: jagan@ccmb.res.in