Which purification protocol is the best?

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Which purification protocol is the best?

Postby exia1995 » Nov 10 2017 9:30 am

Given purification of the same enzyme using 4 diffrerent protocols, based on the concentration, volume and total activity of enzyme from each protocol, which is the best? What do i use as an indicator as to which protocol is the best? Specific enzyme activity or yield?

Protocol A: 100uL, 20mg/mL, Total activity: 100units/s

Protocol B: 100uL, 50mg/mL, Total activity: 10units/s

Protocol C: 500uL, 20mg/mL, Total activity: 100units/s

Protocol D: 100uL, 10mg/mL, Total activity: 1000units/s
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Re: Which purification protocol is the best?

Postby relaxin » Nov 10 2017 9:44 pm

In general, the higher specific activity the better. With high yield and low specific activity, you may lose more when you have to purify the sample with additional steps. It looks like protocol D gives highest specific activity.

What do you mean by 1000 units/s? Specific activity is expressed as units/ug protein.
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Re: Which purification protocol is the best?

Postby exia1995 » Nov 11 2017 8:25 am

Im nt very sure but the question was just set like this and asked us which protocol is the best based on the results of the enzyme for each of them. Looks to me like production of product? I chose D too on the basis of activity
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Re: Which purification protocol is the best?

Postby mdfenko » Nov 11 2017 9:18 pm

simply put, total activity is the amount or yield of enzymatic activity, specific activity is the purity of the enzyme.
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Re: Which purification protocol is the best?

Postby exia1995 » Nov 11 2017 9:29 pm

So would Protocl D be the best answer?
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Re: Which purification protocol is the best?

Postby mdfenko » Nov 12 2017 2:17 pm

protocol d gives the highest specific activity (best purity). that's what i would go for.
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