Letter 7403

Biology of Copper Sulfate

Hello Please can you tell me whether copper sulphate is an enzyme inhibitor, or indeed if it has any affect on the rate of enzyme reactions, in particular the enzyme, catalase? Thank you

h.chichger
- UK

Is copper sulphate a competitive or non comp. inhibitor of catalase? I am a teacher and do you have any references on line to back this up? Thanks

Lucy McCreath
- Cambridge, England

NARINDER SINGH
- Middlesbrough, England

I too am looking for information but I can tell you the answers to your question... first of all look in any text book and you will find that copper... or any other heavy metal disrupts the tertiary bonds in enzymes and therefore alters their active sites, therefore inhibiting the enzyme.

Copper sulphate is a non competitive inhibitor since it has no structural similarity to the substrate and does not bond at the active site.

Hope I have helped a bit..if anyone else has any info regard rate of inhibition etc..

Sara Jaes
-Brighton, UK

Copper (II) sulphate is an irreversible, non-competitive inhibitor of catalase. It is important to note that CuSO4, as most transition metal compounds, is non-competitive because it is so very different to the substrate (H2O2).

Andrew Nowacki
- Jersey, Channel Islands

I am currently doing a piece of course work on copper sulphate and how it acts on enzymes and I have found that it does not actually act as an inhibitor on the enzyme rennin - in fact it is an activator. I also have not been able to find any useful information on activators. Any help?

Lee O'Brian
- England

Don't blame me if this is wrong, but the theory I used for last year's coursework..... the copper (2+) ions in the cuso4 solution combine with the thiol groups in enzymes, breaking the disulphide bonds that give the enzyme coil its shape. This results in ripples of distortion across the molecule to the active site, which is then altered so that the substrate no longer fits into it

Helen Carey
- England

Copper sulphate is a competitive inhibitor of the enzyme catalase. Catalase contains an iron haem group located in the centre of a porphyrin ring which carries out the reaction. Adding copper sulphate displaces the iron from the centre of the ring, as it has a higher stability constant (K stab). Thus, the iron which catalyses the overall reaction is removed and it cannot proceed.

Neil Harrison
I am a Student Studying biochemistry - Carlisle, UK

I am a student and I am doing my AS biology coursework. I have got a question about copper sulphate. When I did the experiment of enzyme-controlled reaction with starch and amylase, I did two set, one set by adding copper sulphate to the reaction and the other one didn't. Why the concentration of starch left is higher when I did not use copper sulphate than I use that? Suppose that copper sulphate is an inhibitor.

Michelle
- Madrid, Spain

I am an a-level student in the UK. For my biology coursework this year I experimented with copper sulphate as an inhibitor on liver catalase. *cough* I had pretty bizarre results, though. I experimented using different conc.s of copper sulphate, soaked pieces of liver in them, chucked hydrogen peroxide all over them and measured the oxygen that came out the other end. You'd think that the lowest concentration of copper sulphate would have the least inhibition, and vice versa, eh? but no...it didn't play fair like that. I used concentrations 2%, 1%, .75%, .5% and .25% copper sulphate by volume: the first four concentrations followed the expected pattern but my .25% concentration always, always inhibited more than the .5%, usually more than the .75%, and in one case it even inhibited as much as the 1% did! I'm at a loss to explain this. Anyone with interesting ideas can reply to me.

Benjamin Denton
- Warminster, Wilts, UK

Those of you doing A-level biology and asking questions: The explanation about iron given above seems to describe a non-competitive enzyme action despite the first sentence. a competitive enzyme somehow blocks the active site with a molecule of similar structure to the intended substrate. The action described on the heam group is a non-competitive action which actually changes the structure of the protein. This is not competition. Interesting side note for this experiment to further confuse you: Copper ions actually slightly catalyse the hydrogen peroxide reaction the CuSo4 is supposed to inhibit. :)

Richard Marsh
- Oxford, UK

After conducting "An Investigation into the effect of varying concentrations of copper sulphate on the germination of cress seeds" I found that from using, 0.0002, 0.002, 0.02 and 0.2 concentrations, the mean length of radical produced after 3 days was progressively lower as concentration increased. All other relevant conditions kept constant.

This leads me to believe that copper sulphate is a noncompetitive inhibitor. I am interested to find out the chemistry behind this and have read the comments of Helen Darey above. Could anyone tell me why the positive copper ions are attracted to the thiol groups involved in disulphide bonds in the enzyme?

Barney Harris
Student - Shropshire, UK

Thank you to all of the above I am an a-level student studying AS biology and thanks to you all I am sure I will get full marks in my planning section.

is Cu2+ a permanent non-competitive inhibitor of catalase? apparently need to know, though I don't know why...

Kattie Lou
student - St Saviour, Jersey, UK

Hydrogen peroxide is used as a substrate to catalyse, but, when H2O2 is entered and reacts with metal ions it can start to decompose under the pressure.

Adam Tomlinson
- Northants, UK

Would it be possible to answer my enquiry, I have scanned the internet and spent hours in the library with little answers. I am researching Enzymes and their particular effect in conjunction with inhibition. My investigation is to study the effect of CuSO4 on pectinase and the substrate of apples. I believe that CuSO4 in a reversible/competitive inhibitor to cataylase, or amylase by studying your posted enquiries. Thank for your sharing of knowledge!

Emily Harris
artist/student - London, Essex, UK

Hi there i am doing a biology lab in which i am mixing hydrogen peroxide with catalase, and copper is being added. Our results showed that the reaction rate slowed down. Is that justified? is copper acting as a competitive or non competitive inhibitor? and why i could not determine if i was right or wrong in my results asap thanks a lot

nina
student - brampton, ontario, canada

I am currently doing a piece of coursework on the effect of CuSO4 on Catalase during the decomposition of H2O2. Qs. Is CuSO4 an inhibitor? Is it competitive or non-competitive? Is it reversible or irreversible? Why does it inhibit the reaction?

Syed Nadir Ahmed
- London, UK

C'mon now, Emily, Nina, Syed :-)

It's disrespectful to the people who have posted here to ignore the effort they have put in already. Unless you phrase your question in terms of what has already been said here, rather than just cutting and pasting your homework question, I doubt that anyone is going to answer.

 
Ted Mooney, P.E.
finishing.com Inc. - Brick, NJ

I am doing coursework into the effect of different concentrations of copper sulphate on the germination of cress seeds but we have too say something about copper tolerance can anyone help as I don't know anything about this?

Megan W.
- Shresbury, Shropshire, UK

Hi, I'm doing an A level chemistry investigation, and was just wondering if anyone can help! If the Cu2+ ions in copper sulphate inhibit catalase (I have found this to be true for many other d-block sulphates such as zinc sulphate, iron sulphate and nickel sulphate)why do the Cu2+ ions in copper oxide (CuO) not inhibit catalase?! Is it something to do with the fact they are bonded with sulphate? HELP!

Susan J.
- London, UK

Hi I'm also a student and I'm doing AS biology, i just started the coursework and i would like to know if copper sulphate can be used as an inhibitor on pectinase (breaking down pectins) its just i read it on a website and I'm not sure its true, any reply would be nice.

James W.
- Telford

I am an AS biology student doing my coursework, and I have looked through previous questions, but as I have noticed, there has been none about the inhibition of yeast using Copper sulphate. I just wondered if anyone would mind giving me something, its just that i have a biological knowledge section of coursework to complete and i can't find any information anywhere, i would appreciate it sooo much!

Roxanne H.
Student - Bishops Stortford, Essex, UK

CuSO4 is indeed a non-competitive, irreversible inhibitor, because it is a heavy metal, the ions fit between the enzyme structure and alter the structure, preventing the enzyme from acting on any substrate.

Rox
- UK

Hi every1

Is copper ions an inhibitor for amylase as well?

Thanks

Jaany Frixtol
- UK

Just a warning, that I'm only an A2 student and what I say may or may not be entirely accurate. You should definitely check up on anything I write here in case it's wrong.

After spending a few hours in the library, I've learned that copper inhibits enzymes by binding with their -SH (sulphydryl) groups. While these are not part of the active site, they are an integral part of the enzyme, and their disruption permanently puts the enzyme out of action. Amylase I THINK is affected by this mechanism. It is irreversible and non competetive inhibition.

Another mechanism seems to involve displacement of the Ca2+ ion in amylase by Cu2+. This again makes the enzyme useless as the calcium is important for the reaction. I think this would be reversible, if the Cu2+ was replaced again by the Ca2+.

This seems to be a remarkably complicated subject. I suspect all we're required to say, at AS and A2 level, is that it's an irreversible non-competetive inhibitor that affects amylase.

Hope that helps.

Corinne J.
- Herts, UK

Hello,

I am an AS student about to do my coursework, my experiment is how CuSO4 acts as an inhibitor using H2O2 and yeast. Im not sure how to go about this any suggestions would be great. ASAP

Stephanie
- London, UK

Does anyone know what CuSO4 solution does to the production of fruit juice production when using pectinase? I have tried experimentally, and it looks like a non-competitive inhibitor. but I don't know if it is reversible or irreversible. If anyone could tell me how I would go about finding out if it is reversible or irreversible, I would be very grateful.

Tony
- Surrey, UK

I understand that copper sulphate in a non competitive irreversible inhibitor but can someone please state where I can find this information for myself, some references from sites on the net to back up these statements.

Thank you.

Lizzie
- Hertfordshire, UK

I'm an A2 student, like most people on this page I have just attempted a coursework on the inhibiting effect of copper sulphate on the decomposition of H2O2...its slightly over due :S

Anyway, I was wondering why we would be told copper ions inhibit only to discover they catalyse...what if in fact they slightly inhibit BUT the leftover sulphur from the copper sulphate is a catalyst for the reaction? would this be a reasonable explanation?

Also, why would copper displace iron from the haem group if iron is more reactive than copper? simply because there is so much more copper in comparison with iron? I would appreciate any help or comments or any other explanation as to why the reaction was not inhibited!!!

Cheers,

Louise N
- Milton Keyens, Eng

Copper sulphate is an inhibitor, it acts efficiently on the enzyme alpha amylase and thus inhibiting the starch degradation by the enzyme.

Vinaykumar. I . Gurav
- Belgaum, Karnataka, India

I am an AS Biology student who is doing a coursework on the effect of copper sulphate on an enzyme based reaction with catalase it's not working out right coz the copper sulphate seems to be acting as an activator instead of an inhibitor?? please help am at my wits end trying to figure out what am doin wrong

Ebby Ayerume
- Barking, Essex, United Kingdom

I have just finished a test of the effect of Copper sulphate on amylase. Strangly, low levels of copper sulphate were seen to inhibit the break down of starch while high levels of copper sulphate didnt just fail to inhibit the reaction but actually proved faster than a reaction with no copper sulphate. This has baffled me, how has the increased levels of copper sulphate actually speeded up the reaction when everything sugests that it shouldnt?

James Miller
- England

I've listened to everyones comments and theorys, but does anyone know how you can demonstrate what type of inhibitor copper sulphate is experimentally?

Sian Jones
- UK

Inhibhition is a complicated process. It takes a lot of balancing factors for it to be able to work as planned. Copper sulphate IS A non-competitive INHIBHITOR but some experiments may go wrong or not as planned because sometimes copper ions, in some conditions such as say difference in temperature or the amounts you are using, starts acting like an activator. The point about equillibriums and balance of the reactions may come into this. Too much copper sulphate will not work. someone mentioned .5 %....thats lots of copper ions and probably relatively less amounts of substrate or enzyme. Think about it. A level should be covering all this right? Im a GCSE student!

KANI V.
- London, UK

HI, im am doing AS biology and my coursework is based on copper sulphate inhibting the rate of which lactase breaks down lactose. Does anyone know of any background information of copper sulphate and why it inhibts this reaction? thanks.

Andre M.
- London, UK

Can anyone tell me about the inhibitory effect of copper sulphate on invertase.

Sindhu a
- Chennai, TN, India

You may find all the answers you wish regarding copper and catalase here:

Orr, C.: Studies on Ascorbic Acid. II. Physical Changes in Catalase Following Incubation with Ascorbate and Copper, Biochem 6, 3000, 1967

Here is the abstract:

Incubation of catalase with either ascorbate or ascorbate and Cu2+ results in degradative changes in the catalase molecule. The effect of ascorbate alone appears to be qualitatively distinct from that of ascorbate in the presence of Cu2+. Electrophoretic and chromatographic analysis of catalase treated with CU~+ and ascorbate revealed that the molecule is extensively degraded with the majority of the resultant fragments being dialyzable. A similar analysis of the effect of ascorbate alone indicated that the degraded fragments were substantially larger and that a small fraction of aggregated or polymerized material occurred. By using [ 14C]ascorbate, significant nondialyzable radioactivity was found associated with the polymerized material suggesting that at least some ascorbate must be bound to catalase. After treatment with ascorbate, or ascorbate and Cu2+, the spectrum of catalase is changed. While there is obvious reduction in the Soret band at 408 mp the shift of this peak to longer wavelengths is almost undetectable. It is concluded that very little, if any, catalase complex I1 is formed under these conditions. Significant spectral changes occur at shorter wavelengths. These have been tentatively interpreted to represent oxidative changes in labile aromatic amino acids. The results strongly support previous data which indicated that the inhibition of catalase by ascorbate, or ascorbate and Cu2+, was the result of . OH or * OnH attack of the enzyme.

If you are going to use any of this, do quote the original Author.

Filip Rabuzin
- Zagreb, Croatia

I want to respond or follow up on this copper sulphate inhibition question

 

I want to start a new thread on a different subject related to metal finishing.