Enzyme Flashcards
List 2 of the biomedical importance of enzyme
Enzymes catalyze chemical reactions that make life on earth possible.
Enzymes participate in breakdown of nutrients to supply energy and chemical building blocks:
Assembly of building blocks into proteins, DNA, membranes, cells, and tissues
Harnessing of energy to power cell motility, neural function, and muscle contraction
Vast majority of enzymes are proteins – what are the exceptions?
notable exceptions are ribosomal RNAs and ribozymes, which are RNA molecules imbued with endonuclease or nucleotide ligase activity
What are some Clinical applications of Studying Enzyme?
§ Ability to detect and to quantify the activity of specific enzymes in blood, other tissue fluids, or cell provides information that complements the physician’s ability to diagnose and predict the prognosis of many diseases.
§ Changes in the quantity or in the catalytic activity of key enzymes can result from genetic defects (due to fail protein transcription), nutritional deficits, tissue damage, toxins, or infection by viral or bacterial pathogens.
§ Biochemists address imbalances in enzyme activity by using pharmacologic agents to inhibit specific enzymes and are investigating gene therapy as a means to remedy deficits in enzyme level or function.
_______ augment (intensify) the capacity of detergents to remove dirt and stains.
Proteases and amylases
Enzymes’ catalytic activity, substrate specificity, and stereospecificity enable them to fulfill key roles related to human health and well-being. What are these?
Proteases and amylases augment (intensify) the capacity of detergents to remove dirt and stains.
Play important roles in producing or enhancing the nutrient value of food products for both humans and animals – protease rennin (breakdown casein) is utilized in the production of cheese; lactase is employed to remove lactose from milk for the benefit of lactose-intolerant persons.
stereospecific enzyme catalysts can be of particular value in the biosynthesis of complex drugs or antibiotics.
Play important roles in producing or enhancing the nutrient value of food products for both humans and animals – _________ is utilized in the production of cheese; __________ is employed to remove lactose from milk for the benefit of lactose-intolerant persons.
protease rennin (breakdown casein)
lactase
Stereospecific enzyme catalysts can be of particular value in the ___________
biosynthesis of complex drugs or antibiotics
§ Enzymes are mostly protein catalysts that _________.
§ Virtually all reactions in the body are mediated by _______.
§ Among the many biologic reactions that are energetically possible, enzymes selectively channel _______ into useful pathways.
increase the rate of reactions without being permanently changed in the overall process, either go back, consumed or alter.
enzymes
reactants (called substrates)
Enzymes contain a ______ called the active site.
§ The active site contains amino acid side chains that participate in _______.
§ The substrate binds the enzyme, forming an ________.
§ Binding is thought to cause a _______ change in the _______ that allows catalysis.
§ _________ complex that subsequently dissociates to ________.
special pocket or cleft
substrate binding and catalysis
enzyme-substrate (ES) complex
conformational (shape), enzyme (induced fit)
Enzyme Substrate (ES) is converted to an enzyme-product (EP), enzyme and product
True or False:
§ Enzymes direct all metabolic events.
§ Enzymes cannot be stop or proceed.
True
False
Enzymes are _______ as a consequence of their participation in a reaction
Enzyme-catalyzed reactions proceed from _______ times faster than non-catalyzed reactions.
______number of molecules of substrate converted to product per enzyme molecule per second – typically is _______ per second.
neither consumed nor permanently altered
10^3–10^8
Turnover number or kcat (catalytic number), 10^2 to 10^4
