Functional definition of the tobacco protoporphyrinogen IX oxidase substrate-binding site
نویسندگان
چکیده
منابع مشابه
Functional definition of the tobacco protoporphyrinogen IX oxidase substrate-binding site.
PPO (protoporphyrinogen IX oxidase) catalyses the flavin-dependent six-electron oxidation of protogen (protoporphyrinogen IX) to form proto (protoporphyrin IX), a crucial step in haem and chlorophyll biosynthesis. The apparent K(m) value for wild-type tobacco PPO2 (mitochondrial PPO) was 1.17 muM, with a V(max) of 4.27 muM.min(-1).mg(-1) and a catalytic activity k(cat) of 6.0 s(-1). Amino acid ...
متن کاملCloning and characterization of a plastidal and a mitochondrial isoform of tobacco protoporphyrinogen IX oxidase.
Protoporphyrinogen IX oxidase is the last enzyme in the common pathway of heme and chlorophyll synthesis and provides precursor for the mitochondrial and plastidic heme synthesis and the predominant chlorophyll synthesis in plastids. We cloned two different, full-length tobacco cDNA sequences by complementation of the protoporphyrin-IX-accumulating Escherichia coli hemG mutant from heme auxotro...
متن کاملThe enzymic conversion of protoporphyrinogen IX to protoporphyrin IX. Protoporphyrinogen oxidase activity in mitochondrial extracts of Saccharomyces cerevisiae.
The oxidation of protoporphyrinogen IX to protoporphyrin IX in yeast cells is enzyme-dependent. The enzyme, protoporphyrinogen oxidase, associated with purified mitochondria isolated from Saccharomyces cerevisiae was solubilized by sonic treatment in the presence of detergent and partially purified. The molecular weight of the enzyme was 180,000 plus or minus 18,000. The purified preparation co...
متن کاملLeishmania major possesses a unique HemG-type protoporphyrinogen IX oxidase
Leishmania major was proposed to either utilize haem from its host or partially synthesize the tetrapyrrole from host provided precursors. However, only indirect evidence was available for this partial late haem biosynthetic pathway. Here, we demonstrate that the LMJF_06_1280 gene of L. major encodes a HemG-type PPO (protoporphyrinogen IX oxidase) catalysing the oxidation of protoporphyrinogen ...
متن کاملThe Enzymic Conversion of Protoporphyrinogen IX to Protoporphyrin IX
The oxidation of protoporphyrinogen IX to protoporphyrin TX in yeast cells is enzyme-dependent. The enzyme, protoporphyrinogen oxidase, associated with purified mitochondria isolated from Saccharomyces cereuisiae was solubilized by sonic treatment in the presence of detergent and partially purified. The molecular weight of the enzyme was 180,000 f 18,000. The purified preparation could be store...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Biochemical Journal
سال: 2007
ISSN: 0264-6021,1470-8728
DOI: 10.1042/bj20061321