PMID- 9305979
OWN - NLM
STAT- MEDLINE
DCOM- 19971023
LR  - 20191210
IS  - 0006-2960 (Print)
IS  - 0006-2960 (Linking)
VI  - 36
IP  - 39
DP  - 1997 Sep 30
TI  - Synthesis of a radioactive azido derivative of thapsigargin and photolabeling of 
      the sarcoplasmic reticulum ATPase.
PG  - 11865-72
AB  - A thapsigargin C8-derivative (ZTG) was synthesized by acylating 
      debutanoylthapsigargin with 4-azido[carboxyl-14C]benzoic acid. ZTG retains the 
      inhibitory activity of thapsigargin (TG) with respect to the Ca2+ ATPase of 
      sarcoplasmic reticulum (SR). Covalent ATPase labeling was obtained by 
      photoactivation of the ZTG azido moiety under conditions optimized to reduce 
      nonspecific association of ZTG with SR vesicles and to approximate a matching 
      ZTG:ATPase stoichiometry. Specific photolabeling of the Ca2+ ATPase with ZTG was 
      obtained with 30% efficiency and was competitively inhibited by TG. Analysis of 
      the labeled protein and its proteolytic fragments demonstrates that the ZTG label 
      is associated covalently with the membrane-bound portion of tryptic subfragment 
      A1, which spans the sequence between Leu253 and Arg324 and includes segments of 
      S3 and S4 in the stalk, the M3 and M4 transmembrane helices, and the intervening 
      lumenal loop. This finding is in agreement with previous spectroscopic 
      observations and mutational analysis.
FAU - Hua, S
AU  - Hua S
AD  - Department of Biochemistry and Molecular Biology, University of Maryland School 
      of Medicine, Baltimore, Maryland 21201, USA.
FAU - Inesi, G
AU  - Inesi G
LA  - eng
GR  - P01HL-27867/HL/NHLBI NIH HHS/United States
PT  - Journal Article
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - Biochemistry
JT  - Biochemistry
JID - 0370623
RN  - 0 (Affinity Labels)
RN  - 0 (Azides)
RN  - 67526-95-8 (Thapsigargin)
RN  - EC 3.6.1.- (Adenosine Triphosphatases)
RN  - EC 7.2.2.10 (Calcium-Transporting ATPases)
SB  - IM
MH  - Acylation
MH  - Adenosine Triphosphatases/chemistry/*metabolism
MH  - Affinity Labels/*metabolism
MH  - Amino Acid Sequence
MH  - Animals
MH  - Azides/*metabolism
MH  - Calcium-Transporting ATPases/metabolism
MH  - Hydrolysis
MH  - Models, Chemical
MH  - Molecular Sequence Data
MH  - Peptide Mapping
MH  - Protein Structure, Secondary
MH  - Rabbits
MH  - Sarcoplasmic Reticulum/*enzymology
MH  - Thapsigargin/*analogs & derivatives/metabolism
EDAT- 1997/10/08 00:00
MHDA- 1997/10/08 00:01
CRDT- 1997/10/08 00:00
PHST- 1997/10/08 00:00 [pubmed]
PHST- 1997/10/08 00:01 [medline]
PHST- 1997/10/08 00:00 [entrez]
AID - bi970105n [pii]
AID - 10.1021/bi970105n [doi]
PST - ppublish
SO  - Biochemistry. 1997 Sep 30;36(39):11865-72. doi: 10.1021/bi970105n.