Enzyme catalase

[darkheavens]

What would happen to the enzyme catalase if it is placed in a 50 degrees celcius solution? Would it partially or be completely denatured?

[TrueLight]

i believe its completely denatured... i read somewhere 40-50 degrees
that would make sense... since it works best at body temp.

[physics]

in the bio book it says at what degree the enzyme would denature i think it would denature

[TrueLight]

did you do an experiment with it? if you did you can see the effect when you do it

[akira88]

Since catalase works in the human body, and the human body functions at 37 degrees celsius, I'm thinking that the enzyme catalase will denature. I don't think there is such a thing as "partially denature"? It either does or doesn't, once it hits past its critical point.

[hhland]

Since catalase works in the human body, and the human body functions at 37 degrees celsius, I'm thinking that the enzyme catalase will denature. I don't think there is such a thing as "partially denature"? It either does or doesn't, once it hits past its critical point.

Those who are referring to the catalase enzyme sac, my boiled liver still gave off a slight reaction this may be due to the fact that I took a piece of liver from the centre of the liver where not all of the enzymes may have been denatured. The enzymes are not "partially denatured" but there are just some enzymes that havnt been denatured yet.

[akira88]

Haha I did this exact SAC except instead of temperature, placed the liver in various pH solutions. It was strange as at a pH of 14, the enzyme catalase worked better than at the pH of :| Weird.

[lexitu]

How do you know that it worked better? Haven't done this prac before....

[akira88]

I did a similar prac at school a couple of weeks ago, but instead of temperature, we placed liver in various pH solutions and observed its reaction rate with hydrogen peroxide. There were plenty of places where there could be errors though, because my school didn't do it very accurate, so it was probably why we had dodgy results.

[darkheavens]

did you do an experiment with it? if you did you can see the effect when you do it

Nah we didn't do an experiment with it at 50 degrees celcius.

Anyone able to explain what happens to the bonds in the enzyme though? Which bonds are broken etc

[happyhappyland]

did you do an experiment with it? if you did you can see the effect when you do it

Nah we didn't do an experiment with it at 50 degrees celcius.

Anyone able to explain what happens to the bonds in the enzyme though? Which bonds are broken etc

At high temperatures the relatively weak hydrogen bonds that form alpha helixes and beta sheets in secondary structures are broken thus the active site of the enzyme has changed making it lose its function. Bonds that form the tertiary structure such as disulfide bonds can also be broken.

Just some side infomation, when enzymes are denatured, their amino acids can be used again it is just the enzyme STRUCTURE that is gone.

[darkheavens]

Ahhhk, thanks happy.

Is it only hydrogen and disulfide bonds that are broken though? No other bonds broken at 50 degrees?

[TrueLight]

you might want to read this

http://books.google.com.au/books?id=2TjAqddKsscC&pg=PA207&lpg=PA207&dq=do+covalent+bonds+of+dna+get+broken+at+high+temperatures&source=bl&ots=7u0X4Dn2AZ&sig=yNcIQ9cqHBEbJuGjGTrx7gIv1Wo&hl=en&ei=XNKcS86kHMqHkQWP99DwDA&sa=X&oi=book_result&ct=result&resnum=8&ved=0CB4Q6AEwBw#v=onepage&q=&f=false

i dont exactly know what the melting temperature of catalase is, might want to check that out
but i know the hydrogen bonding will be affected, whether the whole enzyme starts being degraded and covalent links broken, i doubt it

[happyhappyland]

you might want to read this

http://books.google.com.au/books?id=2TjAqddKsscC&pg=PA207&lpg=PA207&dq=do+covalent+bonds+of+dna+get+broken+at+high+temperatures&source=bl&ots=7u0X4Dn2AZ&sig=yNcIQ9cqHBEbJuGjGTrx7gIv1Wo&hl=en&ei=XNKcS86kHMqHkQWP99DwDA&sa=X&oi=book_result&ct=result&resnum=8&ved=0CB4Q6AEwBw#v=onepage&q=&f=false

i dont exactly know what the melting temperature of catalase is, might want to check that out
but i know the hydrogen bonding will be affected, whether the whole enzyme starts being degraded and covalent links broken, i doubt it

Your link refers heavily to the structure of DNA and its denaturation (? is that a word?). I dont think enzymes can "melt" it is just the breaking of the bonds. Covalent bonds are relatively strong bonds so I would think that temperature does not break those bonds. But from this website http://class.fst.ohio-state.edu/FST822/lectures/Denat.htm it states that pH can break the covalent bonds.