TY - JOUR
T1 - Biochemistry of mitochondrial nitric-oxide synthase
AU - Elfering, Sarah L
AU - Sarkela, Theresa Marie
AU - Giulivi, Cecilia
PY - 2002/10/11
Y1 - 2002/10/11
N2 - We reported that the generation of nitric oxide by mitochondria is catalyzed by a constitutive, mitochondrial nitric-oxide synthase (mtNOS). Given that this production may establish the basis for a novel regulatory pathway of energy metabolism, oxygen consumption, and oxygen free radical production, it becomes imperative to identify unequivocally and characterize this enzyme to provide a basis for its regulation. The mitochondrial localization of mtNOS was supported by following the hepatic distribution of mtNOS, immunoblotting submitochondrial fractions, and immunohistochemistry of liver tissues. mtNOS was identified as brain NOSα by various methods (mass spectrometry of proteolytic fragments, amino acid analysis, molecular weight, pI, and analysis of PCR fragments), excluding the occurrence of a novel isoform or other splice variants. Distribution of mtNOS transcript indicated its occurrence in liver, brain, heart, muscle, kidney, lung, testis, and spleen. In contrast to brain NOS, mtNOS has two post-translational modifications: acylation with myristic acid and phosphorylation at the C terminus. The former modification is a reversible and post-translational process, which may serve for subcellular targeting or membrane anchoring. The latter modification could be linked to enzymatic regulation. These results are discussed in terms of the role that nitric oxide may have in cellular bioenergetics.
AB - We reported that the generation of nitric oxide by mitochondria is catalyzed by a constitutive, mitochondrial nitric-oxide synthase (mtNOS). Given that this production may establish the basis for a novel regulatory pathway of energy metabolism, oxygen consumption, and oxygen free radical production, it becomes imperative to identify unequivocally and characterize this enzyme to provide a basis for its regulation. The mitochondrial localization of mtNOS was supported by following the hepatic distribution of mtNOS, immunoblotting submitochondrial fractions, and immunohistochemistry of liver tissues. mtNOS was identified as brain NOSα by various methods (mass spectrometry of proteolytic fragments, amino acid analysis, molecular weight, pI, and analysis of PCR fragments), excluding the occurrence of a novel isoform or other splice variants. Distribution of mtNOS transcript indicated its occurrence in liver, brain, heart, muscle, kidney, lung, testis, and spleen. In contrast to brain NOS, mtNOS has two post-translational modifications: acylation with myristic acid and phosphorylation at the C terminus. The former modification is a reversible and post-translational process, which may serve for subcellular targeting or membrane anchoring. The latter modification could be linked to enzymatic regulation. These results are discussed in terms of the role that nitric oxide may have in cellular bioenergetics.
UR - http://www.scopus.com/inward/record.url?scp=0037064058&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0037064058&partnerID=8YFLogxK
U2 - 10.1074/jbc.M205256200
DO - 10.1074/jbc.M205256200
M3 - Article
C2 - 12154090
AN - SCOPUS:0037064058
VL - 277
SP - 38079
EP - 38086
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
SN - 0021-9258
IS - 41
ER -