Protein Metabolism: Amino Acid and Protein Synthesis Flashcards
what are the 2 main sources of amino acids?
diet and synthesis
describe the diet as an amino acid source
- essential and non-essential amino acids
- nitrogen/amine groups
describe synthesis as a source of amino acids
- glucose
- citric acid cycle carbons from other pathways
___ concentrations are tightly controlled
amino acid
T or F:
there is an explicit long-term amino acid storage system
false
production of amino acids is dictaed by demands of synthesis since there is no long-term storage system
synthesis of amino acids is a steady state process. what does that mean?
- the body is always producing amino acids
- specific amino acids are produced as needed based on demands
describe the primary amino acid synthesis pathways. what are the 7 precursors?
![](https://s3.amazonaws.com/brainscape-prod/system/cm/199/584/404/q_image_thumb.png?1477422503)
- glycolysis
- 3-phosphoglycerate
- phosphoenolpyruvate
- pyruvate
- pentose phosphate pathway
- ribose 5-phosphate
- erythrose 6-phosphate
- citric acid cycle
- oxaloacetate
- alpha-ketoglutarate
glucose provides ___ backbones for amino acid synthesis
carbon
only ___ out of the 20 common amino acids are synthesized by humans
11
which 2 reaction types are involved in amino acid synthesis?
transaminase and single carbon group reactions
name the amino acid biosynthetic families and group them by metabolic precursor. which are essential? nonessential?
![](https://s3.amazonaws.com/brainscape-prod/system/cm/199/584/872/q_image_thumb.png?1477422768)
starred amino acids are essential (acquired from diet), all others are nonessential (produced in humans)
describe the steps of transcription and translation
- ongoing, steady-state process of protein production
- regulated at several levels
- limited amino acid palette (20)
- extensive transcriptional and post-translational processing
![](https://s3.amazonaws.com/brainscape-prod/system/cm/199/585/031/a_image_thumb.png?1477423173)
describe how DNA is highly organized and compact
- primarily in nucleosome form
- mitosis forms chromosomes (only in chromosomal state when preparing to undergo division)
- 46 chromosomes
what are introns and exons?
- intron - non-coding and spliced from RNA
- exon - encodes for amino acid sequence
what percent of mammalian DNA codes for amino acid chains for proteins?
1.5%
approximately how many human genes are there?
25,000
DNA encodes for ___, which encodes for ___
- mRNA
- polypeptides
what is responsible for transcription, post-transcription modification, and translation?
DNA, pre-mRNA, and mRNA, respectively
what are regulatory regions?
![](https://s3.amazonaws.com/brainscape-prod/system/cm/199/586/220/q_image_thumb.png?1477423849)
areas from which transcription is initiated and regulated
- enhancer/silencer - binding of proteins that promote or inhibit transcription
- promoter region - transcription factor and RNA polymerase binding