Characterization of N-terminal acetylation of α-hemoglobin stabilizing protein (AHSP) by top-down high resolution mass spectrometry of oral fluids from human preterm newborns.

ABSTRACT: The project reports the identification in oral fluid samples of preterm newborns of AHSP (Alpha-hemoglobin Stabilizing Protein), an erythroid-specific protein forming stable complexes with free α-hemoglobin preventing its harmful aggregation and pro-oxidant activity during red blood cell development, following nanoHPLC-high resolution MS proteomic analysis in top-down approach and the determination of its primary structure. Full scan MS spectra deconvolution revealed a monoisotopic mass of the protein inconsistent with the previously reported sequence. The analysis of the MS fragmentation spectra of the protein multicharged ion at 980.29 m/z [M+12H]12+ evidenced a shift of the experimental b-ions which extended from the amino terminus, suggesting the presence of an N-terminal modification in the protein, i.e., the elimination of the iMet1 and the acetylation of the Nα-terminal Ala2, which was confirmed by comparison of the theoretical and experimental MS fragmentation pattern.

INSTRUMENT(S):

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Saliva

SUBMITTER: Claudia Desiderio  

LAB HEAD: Barbara Manconi

PROVIDER: PXD061305 | Pride | 2025-07-18

REPOSITORIES: Pride