De novo sequencing of two new cyclic θ ‐defensins from baboon ( Papio hamadryas ) leukocytes by matrix‐assisted laser desorption/ionization mass spectrometry
peer-reviewed · Rapid Communications in Mass Spectrometry · 2010
| Date | 2010-03-15 |
| Type | peer-reviewed |
| Venue | Rapid Communications in Mass Spectrometry |
| Publisher | Wiley |
| Contribution | downstream-application |
| DOI | 10.1002/rcm.4424 |
| Citations (OpenAlex) | 23 |
| Venue 2-year citedness | 1.80 |
Abstract
Two cyclic theta-defensin peptides were isolated from leukocytes of the hamadryas baboon, Papio hamadryas, and purified to homogeneity by gel electrophoresis and reversed-phase high-performance liquid chromatography. Both peptides had high in vitro activity against Escherichia coli, Listeria monocytogenes, methicillin-resistant Staphylococcus aureus (MRSA) and Candida albicans. Here, we report their de novo sequencing by matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometry (MALDI-TOF/TOF-MS). This was accomplished by combining conventional enzymatic digestion with N-terminal derivatization by 2-sulfobenzoic acid cyclic anhydride (SACA) or 4-sulfophenylisothiocyanate (SPITC) to facilitate the interpretation of fragment ion spectra. In addition to the two cyclic theta-defensins (PhTDs) we also sequenced a novel Papio hamadryas alpha-defensin, PhD-4, which showed high sequence homology to rhesus alpha-defensin RMAD-1 and human alpha-defensin HNP-1.
Methods and tools
- Baboon theta-defensin sequencing: De novo sequencing by MALDI of two new cyclic theta-defensins purified from hamadryas baboon leukocytes, both active in vitro.