GPK enzyme activity is increased either by phosphorylation of these two regulatory subunits by PKA or by Ca+2 binding to the calmodulin subunit; maximal activity requires both.

TLS Online TPP Program

#Id: 7896

#XL - Q Biochemistry

The smallest mitochondrial genomes in Plasmodium, are only about 6 kb, encoding three proteins and the mitochondrial rRNAs.

Arabidopsis thaliana, has 366 kb of mtDNA and cucurbit plants have about 2 Mb of mtDNA.

TLS Online TPP Program

#Id: 7897

#XL - Q Biochemistry

Chloramphenicol, blocks protein synthesis by bacterial and mitochondrial ribosomes

Cycloheximide, does not affect protein synthesis by mitochondrial ribosomes

TLS Online TPP Program

#Id: 7898

#XL - Q Biochemistry

TLS Online TPP Program

#Id: 7899

#XL - Q Biochemistry

Only 22 tRNAs are required for mitochondrial protein synthesis. The normal codon–anticodon pairing rules are relaxed in mitochondria, so that many tRNA molecules recognize any one of the four nucleotides in the third (wobble) position, allowing four codons to be recognized by a single tRNA.

TLS Online TPP Program

#Id: 7900

#XL - Q Biochemistry

Leber’s hereditary optic neuropathy

caused by a missense mutation in the mtDNA gene

encoding subunit 4 of the NADH-CoQ reductase

TLS Online TPP Program

#Id: 7901

#XL - Q Biochemistry

Deletions in mtDNA cause another set of diseases:

Chronic progressive external ophthalmoplegia

Kearns–Sayre syndrome