PMID- 10542053
OWN - NLM
STAT- MEDLINE
DCOM- 20000110
LR  - 20190620
IS  - 0014-2956 (Print)
IS  - 0014-2956 (Linking)
VI  - 266
IP  - 1
DP  - 1999 Nov
TI  - Differential characteristics of human 15-lipoxygenase isozymes and a novel splice
      variant of 15S-lipoxygenase.
PG  - 83-93
AB  - The lipoxygenases (LOs) are a family of nonheme iron dioxygenases that catalyse
      the insertion of molecular oxygen into polyunsaturated fatty acids. Five members 
      of this gene family have been described in man, 5-LO, 12S-LO, 12R-LO, 15-LO and
      15S-LO. Using partially purified recombinant 15S-LO enzyme and cells
      constitutively expressing this protein, we have compared the activity, substrate 
      specificity, kinetic characteristics and regulation of this enzyme to that
      previously reported for 15-LO. 15S-LO has a threefold higher Km, similar Vmax and
      increased specificity of oxygenation for arachidonic acid, and a similar Km but
      decreased Vmax for linoleic acid in comparison to 15-LO. Unlike 15-LO, 15S-LO is 
      not suicide inactivated by the products of fatty acid oxygenation. However, in
      common with other LOs, 15S-LO activity is regulated through calcium-dependent
      association of the enzyme with the membrane fraction of cells. In addition,
      whilst independently cloning the recently described 15S-LO, we identified a
      splice variant containing an in-frame 87-bp deletion corresponding to amino acids
      401-429 inclusive. Modelling of the 15S-LO and subsequent studies with partially 
      purified recombinant protein suggest that the deleted region comprises a complete
      alpha-helix flanking the active site of the enzyme resulting in decreased
      specificity of oxygenation and affinity for fatty acid substrates. Alternative
      splicing of 15S-LO would therefore provide a further level of regulation of fatty
      acid metabolism. These results demonstrate that there are substantial differences
      in the enzyme characteristics and regulation of the 15-LO isozymes which may
      reflect differing roles for the proteins in vivo.
FAU - Kilty, I
AU  - Kilty I
AD  - Discovery Biology, Pfizer Central Research, Sandwich, UK.
      Iain_Kilty@sandwich.pfizer.com
FAU - Logan, A
AU  - Logan A
FAU - Vickers, P J
AU  - Vickers PJ
LA  - eng
SI  - GENBANK/AF149095
PT  - Comparative Study
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - England
TA  - Eur J Biochem
JT  - European journal of biochemistry
JID - 0107600
RN  - 0 (Enzyme Inhibitors)
RN  - 0 (Fatty Acids)
RN  - 0 (Isoenzymes)
RN  - 0 (Lipoxygenase Inhibitors)
RN  - 0 (Recombinant Fusion Proteins)
RN  - EC 1.13.11.33 (Arachidonate 15-Lipoxygenase)
SB  - IM
MH  - Amino Acid Sequence
MH  - Arachidonate 15-Lipoxygenase/*chemistry/genetics/metabolism
MH  - Cells, Cultured
MH  - Chromatography, High Pressure Liquid
MH  - Enzyme Activation
MH  - Enzyme Inhibitors/pharmacology
MH  - Fatty Acids/metabolism
MH  - Humans
MH  - Isoenzymes/antagonists & inhibitors/*chemistry/genetics/metabolism
MH  - Kinetics
MH  - Lipid Peroxidation
MH  - Lipoxygenase Inhibitors
MH  - Models, Molecular
MH  - Molecular Sequence Data
MH  - Organ Specificity
MH  - Protein Conformation
MH  - RNA Splicing
MH  - Recombinant Fusion Proteins/metabolism
MH  - Sequence Alignment
MH  - Sequence Homology, Amino Acid
EDAT- 1999/10/29 00:00
MHDA- 1999/10/29 00:01
CRDT- 1999/10/29 00:00
PHST- 1999/10/29 00:00 [pubmed]
PHST- 1999/10/29 00:01 [medline]
PHST- 1999/10/29 00:00 [entrez]
AID - ejb818 [pii]
AID - 10.1046/j.1432-1327.1999.00818.x [doi]
PST - ppublish
SO  - Eur J Biochem. 1999 Nov;266(1):83-93. doi: 10.1046/j.1432-1327.1999.00818.x.