PMID- 10527498
OWN - NLM
STAT- MEDLINE
DCOM- 19991223
LR  - 20061115
IS  - 0003-2697 (Print)
IS  - 0003-2697 (Linking)
VI  - 274
IP  - 1
DP  - 1999 Oct 1
TI  - Chromogranin A from bovine adrenal medulla: molecular characterization of
      glycosylations, phosphorylations, and sequence heterogeneities by mass
      spectrometry.
PG  - 69-80
AB  - Chromogranin A (CGA) is a member of a family of acidic glycoproteins present in
      endocrine and neuroendocrine tissues. One of its suggested physiological roles is
      being a precursor molecule for several peptide hormons. Further interest in this 
      protein has recently originated from its potential role in pathophysiological
      processes of Alzheimer's disease. The concentration of CGA in the brain has been 
      used for diagnosis of this disease, and CGA as an insoluble deposit has been
      found in the extracellular beta-amyloid plaques. By developing a new purification
      procedure we were able to isolate abundant CGA in high purity from bovine
      chromaffin cells. A MALDI-MS analysis of the intact protein revealed a
      heterogeneous molecular mass of ca. 50 kDa, indicating several structure
      modifications. By use of several subsequent proteolytic/chemical cleavage steps, 
      HPLC isolation, a newly developed deglycosylation procedure, and several MS and
      MS-MS fragmentation approaches, the complete primary structure of CGA including
      four sequence heterogeneities, two O-glycosylations, five phosphorylations, and
      one disulfide bridge could be characterized. For both glycans six different forms
      could be identified. Ser167 was found to be mainly glycosylated by a
      trisaccharide, and Thr231 was found to be mainly glycosylated by a
      tetrasaccharide. Ser81, Ser124, and Ser297 residues were partially
      phosphorylated, whereas Ser372 and Ser377 were found completely phosphorylated.
      Sequence heterogeneities were identified in positions 293 (H/R), 301 (K/E), and
      373 (Q/R) and at the partly missing C-terminal residue. Furthermore, a disulfide 
      bridge between Cys17 and Cys38 was ascertained.
CI  - Copyright 1999 Academic Press.
FAU - Bauer, S H
AU  - Bauer SH
AD  - Department of Chemistry, University of Konstanz, Konstanz, D-78457, Germany.
FAU - Zhang, X Y
AU  - Zhang XY
FAU - Van Dongen, W
AU  - Van Dongen W
FAU - Claeys, M
AU  - Claeys M
FAU - Przybylski, M
AU  - Przybylski M
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Anal Biochem
JT  - Analytical biochemistry
JID - 0370535
RN  - 0 (Chromogranin A)
RN  - 0 (Chromogranins)
RN  - 0 (Disulfides)
RN  - 0 (Peptide Fragments)
RN  - EC 3.4.21.4 (Trypsin)
SB  - IM
MH  - Adrenal Medulla/*chemistry
MH  - Amino Acid Sequence
MH  - Animals
MH  - Cattle
MH  - Chromaffin Granules/*chemistry
MH  - Chromogranin A
MH  - Chromogranins/*chemistry/genetics/isolation & purification
MH  - Disulfides/analysis
MH  - Glycosylation
MH  - Molecular Sequence Data
MH  - Peptide Fragments/chemistry/isolation & purification
MH  - Peptide Mapping
MH  - Phosphorylation
MH  - Protein Conformation
MH  - Protein Processing, Post-Translational
MH  - Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods
MH  - Spectrometry, Mass, Secondary Ion/methods
MH  - Trypsin
EDAT- 1999/10/21 00:00
MHDA- 1999/10/21 00:01
CRDT- 1999/10/21 00:00
PHST- 1999/10/21 00:00 [pubmed]
PHST- 1999/10/21 00:01 [medline]
PHST- 1999/10/21 00:00 [entrez]
AID - 10.1006/abio.1999.4244 [doi]
AID - S0003-2697(99)94244-6 [pii]
PST - ppublish
SO  - Anal Biochem. 1999 Oct 1;274(1):69-80. doi: 10.1006/abio.1999.4244.