5 Written Questions
5 Matching Questions
- Enzyme Inhibition
- Allosteric enzymes
In glycolysis, phosphoenolpyruvate (PEP) is converted to pyruvate by pyruvate kinase. This reaction is strongly exergonic and irreversible; in gluconeogenesis, it takes two enzymes, pyruvate carboxylase and PEP carboxykinase, to catalyze the reverse transformation of pyruvate to PEP. The pyruvate is removed from the mitochondria via a membrane bound protein carrier known as the pyruvate transporter.
These plant organelles have their own DNA like mitochondria. They are normally larger than mitochondria though and they also have a three membrane system.
Alanine (abbreviated as Ala or A) is an α-amino acid with the chemical formula CH3CH(NH2)COOH. It can be synthesized from the pyruvate intermediate of the TCA cycle. The L-isomer is one of the 22 proteinogenic amino acids, i.e., the building blocks of proteins. Its codons are GCU, GCC, GCA, and GCG. It is classified as a nonpolar amino acid. L-Alanine is second only to leucine in rate of occurrence, accounting for 7.8% of the primary structure in a sample of 1,150 proteins.D-Alanine occurs in bacterial cell walls and in some peptide antibiotics.
- d An important control mechanism in metabolism, this is also the route of effect used by many drugs and also of many toxins.
Five key characteristics (of this enzyme)
1.Larger, multi-subunit proteins consisting generally of two different subunits eg. catalytic and regulatory.
2. Substrates bind cooperatively to active sites on catalytic subunits.
3. A plot of v against s produces an S shaped sigmoid curve.
4. Effectors for these enzymes can be inhibiting or activating and their binding can also produce sigmoid curves.
5. Feedback inhibition can occur- the end product of the enzymes pathway can inhibit enzyme activity.
5 Multiple Choice Questions
- The protein of which the microtubules of the eukaryote cytoskeleton are formed.
- These junctions function in the same way as anchoring junctions, linking intercellular cytoskeletons using cadherin. Unlike the anchoring junctions these junctions use the actin filaments not the intermediate filaments to secure the cells.
- The tiny electrically driven motor found in ATP synthase.
Also known as 2-D electrophoresis, begins with 1-D electrophoresis but then separates the molecules by a second property in a direction 90 degrees from the first. In 1-D electrophoresis, proteins (or other molecules) are separated in one dimension, so that all the proteins/molecules will lie along a lane but that the molecules are spread out across a 2-D gel. Because it is unlikely that two molecules will be similar in two distinct properties, molecules are more effectively separated in 2-D electrophoresis than in 1-D electrophoresis.
Abbreviated as(LPS), also known as lipoglycans, are large molecules consisting of a lipid and a polysaccharide joined by a covalent bond; they are found in the outer membrane of Gram-negative bacteria, act as endotoxins and elicit strong immune responses in animals.
5 True/False Questions
Receptor mediated endocytosis →
RME, also called clathrin-dependent endocytosis, is a process by which cells internalize molecules (endocytosis) by the inward budding of plasma membrane vesicles containing proteins with receptor sites specific to the molecules being internalized.
Stroma (fluid), the fluid in between grana, where carbohydrate formation reactions occur in the chloroplasts of plant cells photosynthesizing
α-Ketoglutaric acid →
An intermediate product of the TCA cycle formed after T3 which involves the removal of 2 hydrogen atoms and a molecule of CO₂ being released from isocitrate.Its anion, α-ketoglutarate (α-KG, also called oxo-glutarate) is an important biological compound. It is the keto acid produced by de-amination of glutamate, and is an intermediate in the Krebs cycle.
Special proteins around which DNA is wrapped.
The β sheet (also β-pleated sheet) is the second form of regular secondary structure in proteins, only somewhat less common than alpha helix. Beta sheets consist of beta strands connected laterally by at least two or three backbone hydrogen bonds, forming a generally twisted, pleated sheet. A beta strand (also β strand) is a stretch of polypeptide chain typically 3 to 10 amino acids long with backbone in an almost fully extended conformation. The higher-level association of β sheets has been implicated in formation of the protein aggregates and fibrils observed in many human diseases, notably the amyloidoses such as Alzheimer's disease.