Intro to Cofactors - Video Tutorials & Practice Problems
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1
concept
Intro to Cofactors Concept 1
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2m
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So here we're going to say that some enzymes require the use of a cofactor in order to catalyze a chemical reaction. Well, what's a cofactor? Well, a cofactor is just a non peptide covalent bonded to an enzyme that is essential to its catalytic activity. When we talk about a coenzyme. Well, they can be either inorganic or organic. So remember this means a presence of carbon, an inorganic cofactor just equals a metallic ion like magnesium. An organic cofactor is called a co enzyme. Now, with this idea of an enzyme in a cofactor, we're gonna say that an apoenzyme is basically an inactive enzyme form and a hollow enzyme is the active enzyme. Four, if we take a look here at enzyme activation, we're starting out with an inactive enzyme. This inactive enzyme is our apoenzyme. And here we have a cofactor doesn't look like a metal ion. So it must be our co Enzi remember that a substrate wants to connect to the active site of our enzyme. But as we look, this substrate here doesn't exactly match up with the shape that's here for the enzyme. That's where the cofactor comes into play. The co factor comes in and attaches to that spot because it fits better. And now we have our cofactor and our enzyme connected together, thus activating our enzyme. So here we have our active enzyme which is our hollow enzyme. And we can see now that the substrate, its form better fits this portion of the enzyme. So it can come in and attach there. So it comes in and attaches right there. Doing this helps us to create a structure where we have our enzyme, our cofactor and our substrate altogether. And remember when we have our enzyme and substrate together, that's called our enzyme substrate complex. So this would be when we've activated our enzyme, the substrate can then come in and attach, right. So just remember, not all enzymes work this way but those that do require some type of cofactor, whether it's inorganic or organic to activate itself.
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example
Intro to Cofactors Example 1
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48s
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Which of the following could be a cofactor but not a coenzyme. Remember cofactors can be either inorganic or organic. The organic ones are called co enzymes. So this would be an organic whole factor. The inorganic ones are, are metallic ions. If we look here, we have F ad fa F ad we have N AD plus we have magnesium ion and then we have coenzyme, we'd say here. The only one that represents a metallic ion would be option C the magnesium ion here it is a cofactor but because it's inorganic, meaning it doesn't have carbon attached to it. It is not a coenzyme, right. So again, C would be our final answer.
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Problem
Problem
Indicate which of the following conditions represents an active enzyme.
I. An enzyme after its release of Cu (I) ion used for catalytic activity.
II. A polypeptide chain that is biologically functional.
III. An enzyme that binds to organic factor in the form of Vitamin B2.
IV. None of the following
A
IV only
B
I and II
C
II and III
D
I, II and III
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