Term
| Which 2 AAs become essential if their precursor AA is not present? |
|
Definition
| Cysteine (reqs Methionine), Tyrosine (reqs phenylalanine) |
|
|
Term
| Which 2 AAs are formed in 1 step by direct transamination of a non-AA precursor? |
|
Definition
| Alanine (from pyruvate), Aspartate (from OAA) |
|
|
Term
| Reqd co-factor for transamination? |
|
Definition
|
|
Term
| Where in cell and in which tissues does AA synth occur? |
|
Definition
|
|
Term
| How is glutamate synthesized? |
|
Definition
| From aKG + ammonia + NADPH, via GlutamateDH |
|
|
Term
| Which AAs are synth via urea cycle steps? |
|
Definition
| Glutamine, Glutamate, Arginine |
|
|
Term
| How is Glutamine synthesized? |
|
Definition
| Glutamate+Ammonia, via Glutamine Synthase |
|
|
Term
| How is asparagine synthesized? |
|
Definition
|
|
Term
| Where does the NH4 for asparagine synth come from? |
|
Definition
|
|
Term
| How is Cysteine synthesized? |
|
Definition
| Methionine+Serine, transsulfuration pathway! |
|
|
Term
| What co-factor is necessary for tyrosine synthesis? |
|
Definition
|
|
Term
| Which 2 AAs are interchangeable via methylation by N5,N10-CH2-THF? |
|
Definition
| Serine, Glycine (Glycine+CH2=Serine) |
|
|
Term
| Which AA can 3PGA from glycolysis be used to synth? |
|
Definition
|
|
Term
| How can Glycine be synth de novo? |
|
Definition
| CO2 + NH3 + N5,N10-CH2-THF + NADH |
|
|
Term
| How does benzoic acid treat ammonia toxicity? |
|
Definition
| Takes the ammonia grp from glycine to form hippuric acid which is then excreted |
|
|
Term
| How is Arginine synthesized? |
|
Definition
| CarbamoylP+Ornithine+Aspartate (via urea cycle) |
|
|
Term
| Which AA is essential in children but not adults? |
|
Definition
|
|
Term
| Which AA can be synth from a Krebs intermediate? |
|
Definition
|
|
Term
| Glutamate plays a role in the synth of which AAs? |
|
Definition
| Glutamine, Aspartate, Asparagine, Alanine, Proline |
|
|
Term
| What are the catecholamines? |
|
Definition
| DOPA, dopamine, norepi, epi |
|
|
Term
| Where are the catecholamines synth? |
|
Definition
|
|
Term
| First step of catecholamine synth? |
|
Definition
| Tyrosine Hydroxylase rxn (rate limiting) |
|
|
Term
| What co-factor is reqd for rate limiting step of catecholamine synth? |
|
Definition
| THB (Tyrosine Hydroxylase rxn) |
|
|
Term
| What type of rxn are hydroxylases and which co-factor do they require? |
|
Definition
| Mixed fxn oxidase, req THB and O2 (incl phenylalanine hydroxylase and tyrosine hydroxylase) |
|
|
Term
| Which co-factor is reqd for the conversion of DOPA to dopamine? |
|
Definition
|
|
Term
| Fxn of dopamine and where in the brain is it synth & used? |
|
Definition
| NT; Controls coordination, motor control, mood; Substantia Nigra |
|
|
Term
| What does a deficiency of dopamine cause and how? |
|
Definition
| Parkinsons; Substantia Nigra is damaged --> cant make or use dopamine. |
|
|
Term
|
Definition
| Cause undetermined, maybe toxins/iron -->free radical damage; Amines (incl NTs) being removed by monoamine oxidases; ComplexIII inhibition--> accumulation of Q which oxidizes. |
|
|
Term
| How could the respiratory chain contribute to neurological disease? |
|
Definition
| Destruction of CIII could --> Parkinsons |
|
|
Term
| How is Parkinsons treated? |
|
Definition
| Give dopa since dopamine is charged at physiological pH and cant cross BBB. |
|
|
Term
| Which co-factor and metal are reqd for conversion of dopamine to its product? |
|
Definition
| Vit C & Copper; -->NorEpi |
|
|
Term
|
Definition
| Regulates blood flow and heart beat, vasodilator. |
|
|
Term
| Which co-factor and metal are reqd for conversion of NorEpi to its product? |
|
Definition
|
|
Term
| Which co-factors are reqd in the catecholamine synth pathway? |
|
Definition
|
|
Term
| Which AAs --> Glutathione? |
|
Definition
| Glutamate, Glycine, Serine |
|
|
Term
| Tryptophan is a precursor to which biomolecules? |
|
Definition
| Pyruvate, Nicotinic Acid (NAD/NADP), Serotonin-->Melotonin |
|
|
Term
| What is caused by a def of tryptophan? |
|
Definition
| Pellagra=energy impairment, neuro/vascular deficits, death; occurs when corn is main protein source. |
|
|
Term
| Tryptophan is a precursor to which biomolecules? |
|
Definition
| Pyruvate, Nicotinic Acid (NAD/NADP), Serotonin-->Melotonin |
|
|
Term
| What is caused by a def of tryptophan? |
|
Definition
| Pellagra=energy impairment, neuro/vascular deficits, death; occurs when corn is main protein source. |
|
|
Term
| Which AAs are precursors to Creatine? |
|
Definition
| Glycine, Arginine (SAM reqd for methylation) |
|
|
Term
| How is creatine P produced and what is its fxn? |
|
Definition
| Creatine + ATP --> Creatine-P + ADP; Can be used to temporarily produce ATP in emergency anaerobic conditions. |
|
|
Term
| Clinical significance of CPK? |
|
Definition
| Diff isoforms useful for diagnosis ie brain (stroke), heart (MI). |
|
|
Term
| Clinical significance of Creatinine? |
|
Definition
| Excess Creatine-P breaks down --> Creatinine --> excreted in urine; somewhat indicative of kidney fxn/urine flow. |
|
|
Term
| Which co-factors are reqd for the tryptophan--> serotonin--> melatonin pathway? |
|
Definition
|
|
Term
|
Definition
| NT - "feel good", powerful vasoconstrictor - important in BP regulation. |
|
|
Term
|
Definition
| Helps set our 24 hr clock, v. powerful antioxidant esp in brain. |
|
|
Term
| What could a deficiency of DHB reductase cause? |
|
Definition
| Hyperphenylalomia (phenylalanine-->tyrosine), decr Catecholamine (tyrosine-->Cats) and Serotonin (tryptophan-->serotonin) pdxn. |
|
|
Term
| Which biochemicals are synth via decarboxylation rxns and what co-factor is reqd? |
|
Definition
| GABA (glutamate), Histamine (Histidine), Ethanolamine (Serine), Dopamine (DOPA), Serotonin (5HT), Putrescine (Ornithine); PLP/B6 |
|
|
Term
|
Definition
| Vasodilator (allergies/immuno attacks), promotes secretion of pepsin/HCl in stomach. |
|
|
Term
|
Definition
| Precursor to spermine/spermidine which are DNA binding polyamines (bind and stabilize DNA during cell replication) |
|
|
Term
| Precursor of Nitric Oxide and necessary co-factor? |
|
Definition
|
|
Term
|
Definition
| Critical vasodilator, major regulator of blood pressure/flow, powerful anti-bac behavior, can be NT; in all tissues but lrgst amt in brain. |
|
|
Term
| Rate limiting step of heme synthesis and how is it regulated? |
|
Definition
| SuccCoA+Glycine-->ALA via ALA Synthase (B6 reqd); inhib by heme. |
|
|
Term
|
Definition
| 1)Carry CO2, 2)Cytochromes ie cyt p450, 3)Catalase, 4)e- transfer enzymes, 5)Enzymes involved in prostaglandin synth. |
|
|
Term
| How does heme inhibit ALA Synthase? |
|
Definition
| Blocks translation of mRNA, blocks import of ALAs into mito, destabilizes protein-->degradation. |
|
|
Term
| Precursors of heme synth and where do they come from? |
|
Definition
| SuccCoA- TCA cycle, Methionine, Threonine, Isoleucine, Valine. Glycine - Serine or de novo from CO2+NH3+N5,N10-CH2-THF. |
|
|
Term
| Where in cell does heme synth occur? |
|
Definition
| 1st and last step in mito, rest in cyto. |
|
|
Term
| In which tissues is heme synth? |
|
Definition
| All tissues but most in: Erythropoietic tissue (--> hemoglobin), Liver (-->cytochromes) |
|
|
Term
|
Definition
| Stimulates Fenton and Haber-Weiss rxns to produce hydroxyl radicals. |
|
|
Term
| Why does lead --> anemia? |
|
Definition
| Inhib Heme synth @ 2 steps (ALA dehydrotase, ferrochelatase) |
|
|
Term
| What are porphyrias? symptoms? |
|
Definition
| Def in some part of heme pathway, can be activated by energy of sunlight-->ROS; neurological disturbances, GI probs, anemia, rash. |
|
|
Term
| Where does most of heme breakdown occur? |
|
Definition
| Spleen (heme-->biliverdin-->bilirubin) |
|
|
Term
| What is bilirubin conjugation? |
|
Definition
| Glucose grps put on bilirubin to make it more soluble. |
|
|
Term
| What does accumulation of bilirubin cause? |
|
Definition
| Jaundice, high levels are toxic-->attack brain. |
|
|
Term
| What would cause excess bilirubin to accumulate in blood and how is source of problem determined? |
|
Definition
| 1)Excessive RBC lysis, 2)Recent transfusion, 3)Possibly liver disease bc location of conjugating enzyme, 4)Blocked bile flow. Assay direct (conjugated) or indirect (unconjugated) - if direct due to blocked bile flow, if indirect due to prob w conjugating enzyme. |
|
|
Term
| Which tissues have energy reserves and what form is the energy in? |
|
Definition
| Adipose (triglycerides), Nuscle (glycogen), Liver (glycogen/triglycerides) |
|
|
Term
| Muscle's preferred energy source? |
|
Definition
| KBs, FAs, Glucose when exercising. |
|
|
Term
| Liver's preferred energy source? |
|
Definition
| FAs, glucose only when v well fed. |
|
|
Term
| Which tissues export lactic acid? |
|
Definition
|
|
Term
| Energy exported by adipose tissue? |
|
Definition
|
|
Term
| How does exercising muscle stay energized? |
|
Definition
| Lactic acid--> liver--> gluconeogenesis--> glucose back to muscle (Cori cycle) |
|
|
Term
| What forms of energy does the liver export? |
|
Definition
| Glucose (from gluconeogenesis, glycogen breakdown), Ketone Bodies (when OAA depleted from TCA cycle), Triglycerides (exported as VLDL to be stored in adipose tissue) |
|
|
Term
| Fates of G6P injected into liver? |
|
Definition
| 1)Glyolysis-->Pyruvate, 2)Stored as glycogen, 3)Goes back to glucose. |
|
|
Term
| What is happening during the starved state thats not during basal state? |
|
Definition
| Gluconeogenesis is only source of glucoce since liver and muscle glycogen depleted, Brain using KBs as fuel, Ketone bodies are primary product of FA oxdn as OAA is depleted from TCA. |
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