Multienzyme complex
In molecular biology, a multienzyme complex is a protein complex containing several copies of one or more enzymes packed into one macromolecular assembly. Multienzyme complexes carry out a single or multi-step biochemical reaction taking place within cells. It allows the cell to segregate certain biochemical pathways into one place in the cell.[1]
Examples include pyruvate dehydrogenase, fatty acid synthetase, glutamine synthetase, proteasome, rubisco.
A multienzyme complex that functions in the histidine biosynthesis pathway has been studied at the biochemical and genetic level in the fungus Neurospora crassa. A gene (His-3) was found to encode a protein that functions as a multienzyme complex having three distinct enzymatic activities in the biosynthesis pathway.[2] A genetic analysis of mutants defective in the N. crassa histidine pathway indicated that the individual activities of the multienzyme complex occur in discrete regions of the His-3 genetic map. This finding suggested that each of the activities of the multienzyme complex are encoded separately from each other, but within the same gene.[2] Some His-3 mutants were also found that lacked all three activities simultaneously, suggesting that some mutations can cause loss of function of the whole multienzyme complex.
See also
[edit]References
[edit]- ^ Neuman, Nicole (2016). "The Complex Macromolecular Complex: Trends in Biochemical Sciences". Trends in Biochemical Sciences. 41 (1): 1–3. doi:10.1016/j.tibs.2015.11.006. PMID 26699226.
- ^ a b Ahmed A. Organization of the histidine-3 region of Neurospora. Mol Gen Genet. 1968;103(2):185-93. doi: 10.1007/BF00427145. PMID 4306011