De novo sequencing of two new cyclic theta-defensins from baboon (Papio hamadryas) leukocytes by matrix-assisted laser desorption/ionization mass spectrometry.
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.
Institute of Bioanalytical Chemistry, Center for Biotechnology and Biomedicine, Faculty of Chemistry and Mineralogy, Leipzig University, Deutscher Platz 5, 04103 Leipzig, Germany.
Christin
C
Stegemann
Elena V
EV
Tsvetkova
Galina M
GM
Aleshina
Robert I
RI
Lehrer
Vladimir N
VN
Kokryakov
Ralf
R
Hoffmann
D000818:Animals; D001419:Bacteria / Q000187:drug effects; D001557:Benzenesulfonates / Q000737:chemistry; D001565:Benzoates / Q000737:chemistry; D002176:Candida albicans / Q000187:drug effects; D003198:Computer Simulation; D023082:Defensins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D017879:Isothiocyanates / Q000737:chemistry; D007962:Leukocytes / Q000737:chemistry*; D008826:Microbial Sensitivity Tests; D048529:Papio hamadryas / Q000097:blood* / Q000235:genetics; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D010449:Peptide Mapping; D017386:Sequence Homology, Amino Acid; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D023084:alpha-Defensins / Q000737:chemistry / Q000235:genetics
D001557:Benzenesulfonates; D001565:Benzoates; D023082:Defensins; D017879:Isothiocyanates; D010446:Peptide Fragments; D023084:alpha-Defensins; C450142:theta-defensin; C015308:4-isothiocyanatobenzenesulfonate; C028022:2-sulfobenzoic acid cyclic anhydride