Category
Biochemistry
Molecules, metabolism, enzymes and laboratory markers.
Subcategories
Glycolysis, gluconeogenesis, glycogen and the pentose phosphate pathway.
Lipid MetabolismFatty acids, ketones, cholesterol and lipoproteins.
Amino Acids and ProteinsProtein structure, amino acid metabolism and the urea cycle.
Nucleotide MetabolismPurine and pyrimidine synthesis, salvage and degradation.
Enzymes and BioenergeticsEnzyme kinetics, regulation, ATP and the electron transport chain.
Vitamins and CofactorsWater and fat soluble vitamins, trace elements and their coenzyme roles.
Molecular BiologyDNA, RNA, transcription, translation and genetic techniques.
Inborn Errors of MetabolismStorage disorders and enzyme deficiencies presenting in childhood.
Clinical BiochemistryLaboratory tests, enzymes and markers used in diagnosis.
Entries in Biochemistry
Adenosine diphosphate
A nucleotide formed when ATP loses one phosphate group.
Alanine aminotransferase
A liver-associated enzyme measured in liver function testing.
Nonpolar, polar, acidic and basic, determined by the R group
A memory aid for grouping amino acids by side chain.
Transamination collects it, glutamine transports it, the urea cycle removes it
A memory aid for how nitrogen is moved and disposed of.
Folate, thymidylate, purine and ribonucleotide reductase pathways
A memory aid for where antimetabolite drugs act.
Aspartate aminotransferase
An enzyme found in liver, muscle and other tissues.
Adenosine triphosphate
A high-energy molecule used as a cellular energy currency.
Glycolysis, the Krebs cycle and oxidative phosphorylation
A memory aid for the stages of cellular energy production.
Cholesterol to bile acids via 7-alpha-hydroxylase, the rate-limiting step
A memory aid for bile acid production and its regulation.
SNoW DRoP: Southern DNA, Northern RNA, Western Protein
A mnemonic for the three blotting techniques and what each detects.
Leucine, isoleucine and valine, metabolised in muscle not liver
A memory aid for the branched chain amino acids and maple syrup urine disease.
Troponin is the standard, rising at 3 to 6 hours and remaining raised for days
A memory aid for the timing of cardiac markers after infarction.
G1, S, G2 and M, with checkpoints controlled by cyclins and p53
A memory aid for the phases of the cell cycle and their checkpoints.
DNA to RNA to protein, by replication, transcription and translation
A memory aid for the flow of genetic information.
Chylomicrons carry dietary fat, VLDL endogenous fat, LDL delivers cholesterol, HDL returns it
A memory aid for the lipoprotein classes and their roles.
Acetyl-CoA to mevalonate via HMG-CoA reductase, the rate-limiting step
A memory aid for the cholesterol synthetic pathway and its regulation.
Hydroxylation requires vitamin C, then glycosylation, triple helix formation and cross-linking
A memory aid for the steps of collagen production.
Cori cycle carries lactate; the alanine cycle also carries nitrogen
A memory aid for the two cycles returning muscle carbon to the liver.
C-reactive protein
An inflammatory marker measured in blood tests.
A defective chloride channel causes thick secretions in every exocrine organ
A memory aid for the molecular defect in cystic fibrosis.
Each pathway repairs a different kind of damage
A memory aid for the DNA repair pathways and the diseases of their failure.
Semi-conservative, bidirectional, with leading and lagging strands
A memory aid for the enzymes and features of DNA replication.
Cyclo-oxygenase makes prostaglandins; lipoxygenase makes leukotrienes
A memory aid for the arachidonic acid pathways.
The standard adult reference values for the basic metabolic panel
A memory aid for the normal ranges of common biochemistry results.
Four complexes pumping protons, and ATP synthase using the gradient
A memory aid for the complexes of the respiratory chain and their inhibitors.
Most B vitamins are coenzyme precursors for specific reaction types
A memory aid for which vitamin becomes which coenzyme.
What happens to Km and Vmax distinguishes them
A memory aid for competitive, non-competitive and uncompetitive inhibition.
Km reflects affinity and Vmax reflects capacity
A memory aid for Michaelis-Menten kinetics and enzyme inhibition.
Each tissue releases a characteristic enzyme profile when damaged
A memory aid for which enzyme indicates which tissue.
Allosteric control, covalent modification, and changes in enzyme quantity
A memory aid for how enzyme activity is controlled.
PVT TIM HaLL: Phenylalanine, Valine, Threonine, Tryptophan, Isoleucine, Methionine, Histidine, Leucine, Lysine
A mnemonic for the nine essential amino acids.
ADEK: absorbed with fat, stored in the body, and capable of toxicity
A mnemonic for the fat soluble vitamins and their functions.
Saturated, monounsaturated and polyunsaturated, with omega-3 and omega-6 essential
A memory aid for the types of dietary fatty acid.
Carnitine shuttles long chain fatty acids into mitochondria for beta oxidation
A memory aid for beta oxidation and its requirements.
Cytoplasmic synthesis from acetyl-CoA using NADPH, with acetyl-CoA carboxylase rate limiting
A memory aid for how fatty acids are made.
Folate donates one carbon units for thymidine and purine synthesis
A memory aid for folate metabolism and the drugs that block it.
Both enter glycolysis, and blocks in either pathway cause distinct disorders
A memory aid for the metabolism of the other dietary sugars.
Loss of NADPH leaves red cells defenceless against oxidative stress
A memory aid for glucose-6-phosphate dehydrogenase deficiency and its triggers.
Transcriptional, post-transcriptional, translational and post-translational
A memory aid for the levels at which gene expression is controlled.
Dominant appears in every generation; recessive skips; X-linked spares father to son
A memory aid for recognising modes of inheritance from a pedigree.
Pyruvate carboxylase, PEP carboxykinase, fructose-1,6-bisphosphatase and glucose-6-phosphatase
A memory aid for the four enzymes that bypass the irreversible steps of glycolysis.
Glycogen synthase builds; glycogen phosphorylase breaks down
A memory aid for glycogen synthesis and breakdown.
Von Gierke, Pompe, Cori and McArdle, by the organ affected
A memory aid for the main glycogen storage diseases.
Ten steps converting glucose to two pyruvate, with a net gain of two ATP
A memory aid for the key steps and regulation of glycolysis.
Begins and ends in the mitochondrion, with ALA synthase rate limiting
A memory aid for haem synthesis and where the porphyrias arise.
Glycated haemoglobin
A blood marker reflecting average blood glucose over roughly the previous two to three months.
Cystathionine beta synthase deficiency, resembling Marfan syndrome with thrombosis
A memory aid for the features of homocystinuria.
Insulin stores in the fed state, glucagon mobilises in the fasted
A memory aid for the opposing actions of insulin and glucagon.
A receptor tyrosine kinase acting through IRS and PI3K to recruit GLUT4
A memory aid for how insulin acts at the cellular level.
Liver, bone, placenta or gut, distinguished by GGT and clinical context
A memory aid for finding the source of a raised ALP.
Different molecular forms of the same enzyme, characteristic of different tissues
A memory aid for the concept and clinical use of isoenzymes.
Made in the liver from acetyl-CoA, used by brain, heart and muscle
A memory aid for ketone production and use.
Acetyl-CoA is oxidised, generating NADH, FADH2 and GTP
A memory aid for the yield and role of the citric acid cycle.
Lactate dehydrogenase
An enzyme involved in the conversion between lactate and pyruvate.
Hormone sensitive lipase releases it, albumin carries it, carnitine admits it
A memory aid for how stored fat is mobilised and transported.
Transaminases indicate hepatocellular injury; ALP and GGT indicate cholestasis
A memory aid for interpreting the liver enzyme pattern.
Enzyme deficiency causes substrate accumulation within lysosomes
A memory aid for the main lysosomal storage diseases.
Maternally inherited, affecting the most energy dependent tissues
A memory aid for the features and inheritance of mitochondrial disease.
Silent, missense, nonsense and frameshift, in order of severity
A memory aid for the classes of DNA mutation and their consequences.
Nicotinamide adenine dinucleotide
An electron carrier involved in redox reactions and metabolism.
Tyrosine gives catecholamines, tryptophan gives serotonin, glutamate gives GABA
A memory aid for which amino acid gives rise to which neurotransmitter.
Nine conditions in the UK programme, taken at day 5
A memory aid for the conditions detected on the newborn blood spot.
Intake minus loss, positive in growth and negative in catabolism
A memory aid for interpreting nitrogen balance.
Purines are built onto the ribose; pyrimidines are built first then attached
A memory aid for de novo purine and pyrimidine synthesis.
Folate carries one carbon units; B12 transfers the methyl group to homocysteine
A memory aid for the folate and B12 methylation cycle.
Organic acidaemias cause acidosis with a raised anion gap; urea cycle defects cause alkalosis
A memory aid for distinguishing the two groups of metabolic crisis in neonates.
Twice the sodium plus urea and glucose
A memory aid for calculating and interpreting plasma osmolality.
Electrons pass down the chain, pumping protons that drive ATP synthase
A memory aid for the electron transport chain and chemiosmosis.
NAPQI depletes glutathione, causing centrilobular necrosis
A memory aid for the mechanism and monitoring of paracetamol toxicity.
Produces NADPH and ribose-5-phosphate without making ATP
A memory aid for the products and purpose of the pentose phosphate pathway.
Phenylalanine hydroxylase deficiency, so phenylalanine accumulates and tyrosine becomes essential
A memory aid for the biochemistry of phenylketonuria.
Denature, anneal, extend, repeated in cycles
A memory aid for the steps of PCR.
Ammonia from deamination is converted to urea in the liver
A memory aid for nitrogen disposal.
Primary sequence, secondary local folding, tertiary three-dimensional shape, quaternary subunits
A memory aid for the four levels of protein structure.
Pure As Gold: purines are Adenine and Guanine; the rest are pyrimidines
A mnemonic for distinguishing purines from pyrimidines.
Xanthine oxidase produces uric acid; HGPRT salvages purines
A memory aid for purine degradation and its disorders.
Irreversibly converts pyruvate to acetyl-CoA, requiring five cofactors
A memory aid for the enzyme linking glycolysis to the Krebs cycle.
Most abnormal results are explained before the sample reaches the analyser
A memory aid for the pre-analytical factors that distort biochemistry results.
Messenger carries, transfer delivers, ribosomal builds
A memory aid for the types of RNA and what each does.
Each is a cofactor whose loss produces a recognisable syndrome
A memory aid for the clinically important trace element deficiencies.
Aldose reductase converts glucose to sorbitol, which is trapped inside cells
A memory aid for the polyol pathway and diabetic complications.
Unfavourable reactions are driven by coupling them to ATP hydrolysis
A memory aid for free energy and coupled reactions.
Wet beriberi, dry beriberi and Wernicke-Korsakoff syndrome
A memory aid for the presentations of vitamin B1 deficiency.
Timing, binding proteins, assay interference and acute illness all distort results
A memory aid for the common traps in endocrine biochemistry.
Zinc, copper, iodine, selenium and chromium, each with a characteristic syndrome
A memory aid for the essential trace elements and their deficiency states.
Transcription in the nucleus, processing, then translation on ribosomes
A memory aid for the steps of gene expression.
Most are for monitoring rather than diagnosis or screening
A memory aid for the common tumour markers and their uses.
Vision, epithelium and differentiation, with teratogenicity in excess
A memory aid for the roles of vitamin A and the dangers of excess.
B12 releases folate from its methylated form
A memory aid for the methyl trap and why B12 must be replaced first.
Collagen hydroxylation, antioxidant activity and iron absorption
A memory aid for the roles of ascorbic acid.
Skin to liver to kidney, with calcitriol acting mainly on the gut
A memory aid for the vitamin D pathway and its effects.
Fat-soluble ADEK and the water-soluble B vitamins and C
A memory aid for the classic vitamin deficiency syndromes.
Cofactor for gamma-carboxylation of factors II, VII, IX and X plus proteins C and S
A memory aid for the role of vitamin K in clotting.
The B group and vitamin C, largely unstored and excreted in urine
A memory aid for the water soluble vitamins and their coenzyme roles.
Wilson accumulates copper; haemochromatosis accumulates iron
A memory aid for the two classic metal overload disorders.