biol+3+summary+notes-enzymes+and+DNA

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//__**Describe the relationship between enzymes and ATP in reactions? **__//

- All reactions require some level of energy to occur. However the amount of energy required to start the reaction (**activation energy**) decreases when enzymes are present. This energy in the cell comes from the breaking of the high energy, terminal phosphate bond of ATP. Thus enzymes lower the amount of ATP required in a reaction for it to occur.

- ATP can also act as a coenzyme in reactions. That is, it associates with the enzyme and aids its activity. In certain cases, the phosphate bond broken in the formation of ADP from ATP can attach to the enzyme. This can activate substrates and help facilitate the reaction.

Something else: In the synthesis of enzymes (proteins) mutations can sometimes occur resulting in changes in primary structure. This results in the enzyme have a different shape. Sometimes this "mutated" enzyme can bond to other subtrates, which can cause trouble for cells/body.

RD

Enzymes speed up reactions. When an enzymes is placed with its reactant a product is produced. For example amylase is an enzyme and it is involved with the breakdown of starch into maltose. This reaction can occur under multiple temperature. The temperature under which a chemical reaction takes places dierectly affects the __rate__ of that reaction. Temperarute increases the rate of chemical reactions. when the breakdown of starch to maltose is tersted in multiple temperatures different results will be produced. The solution with the higher temperature will produce more maltose at the same time as a solution producing maltose at a lower temperature. When two or more temperatures begin to produce the product at a constant rate this comes down to all of the reactants being converted into the product. The product is still being produced within all experimental solutions but just at a constant rate. DV
 * Enzymes; the rate at which their produced vs. the quantity**

= Primary Structure = Amino acids are assembled in a sequence of chains, peptide chains and polypeptide chains. There are 20 different amino acids therefore there are millions of possible amino acid sequences. Bonds between amino acids are formed by condensation polymerization and water is lost. Genes are the sections of DNA that code for proteins (e.g. A C G), if there is an incorrect gene present their will initially be a mutation (e.g. A G G instead of A C G). If there is a mutation in the gene sequence there will be an incorrect amino acid. Due to the mutation in the amino acid this means that there will be a different primary structure (sequence of amino acids) hence an incorrect protein is produced equaling in an INCORRECT ENZYME, and we all know where that leads to...


 * Factors affecting enzyme activity**

A variety of factors can affect the rate of enzyme activity. Enzymes have optimal conditions (temperature and pH) which they work under. Enzyme activity is at its maximum when the enzyme is in optimal conditions. When enzymes are not in optimal conditions enzyme activity is lower than the maximum activity rate. In humans, enzymes tend to work best between 35-40°C and a pH range of 6-8. Some microorganisms e.g. bacteria, have enzymes that are able to function in temperatures as high as 90°C and even boiling water!

When an enzyme and the substance it is breaking down or forming are placed in a solution, eventually the reaction will end and all of the product will have been produced. At a higher temperature, the molecules will vibrate faster and reactions occur quicker, therefore the end amount of product will be reached quicker.
 * Enzymes and substrates**

**__Optimum Temperature:__** Enzymes work best under distinct envirnoments. as already clarified, temperature affects the the effects of enzymes and how efficient they are in performing their required roles. Enzymes become most efficient under what is known as //optimum temperature.// Which is the temperature at which te enzyme's catalytic activity is greatest. In humans, the range of optimum temperature is 35-40 degrees c  elsius. Some bacteria have enzymes that work efficiently as high as 90 degrees celsius. Please can you clarify on your last sentence. my understanding is that after optimal temperature ( approx. 37 degree celsuis) an enzyme will begin to denature. GR  //I will answer this. Optimal temperature can vary between different organisms. Some bacteria live in an environment that is 100oC, so it woul make sense that their enzymes have an optimal temperature of 100oC. VM//

__The active site__ Each enzyme provides an **active site** (the part of the molecule that interacts with the substrate) allowing substrates to combine and form new products. Active sites are highly specific, meaning that they have a shape that compliments the substrate. When enzymes are mutated, the shape of the active site can be changed and therefore allow a different protein to bind to it, changing outcome of the product. ATP can be considered a co-enzyme in relation to the binding of substrates as it is required for enzyme activity, giving the reaction energy to take place.



Occasionally the end product of a biochemical pathway is an inhibitor to one of the enzymes involved in creating the product. This may seem funny or strange but this is the case for isoleucine (the product of threonine). Therefore, in general, there can be an enormous amount of substrate available but the product might not be made because it itself is an inhibitor of an enzyme involved in its own synthesis. Obviously the product can’t cut off all means for its own production otherwise it wouldn’t be produced at all, but it can impede on a high percentage of enzymes slowing its production and even momentarily halting its production. The only way in which a product will continually be produced is if there is no inhibitor in the way.
 * Product suicide **

As temperature rises, it gives reacting molecules more energy. There is a certain temperature at which an enzyme’s catalytic temperature is at its greatest. The optimal temperature for enzymes is usually around 37.5 oC (human body temperature). Any temperature above the optimal level will cause the enzyme to break down (denature).
 * Temperature**

=**Proteomes**= ====- a proteome is the collection of proteins found in a particular cell type. (cell, tissue or organism) - proteomes are larger than genomes, especially in eukaryotes, as there are more proteins than genes. - the area of study dedicated to understanding the structure of proteins and their diverse function, is called proteomics.====

- Proteomics has largely been practiced through the separation of proteins by two dimensional gel electrophoresis.
=Proteomes=

A cell has many proteins, all of the proteins have different functions and structure. All of these proteins are referred to as Proteomes. This includes all the proteins found in your body. Did you know that this area of study is referred to as Proteomics? Very interesting stuff..!

=**The Perfect Packet**=

== DNA is like a perfect packet of Derwent coloured pencils (the packet being the genome). Just imagine, for the sake of this exercise, that these pencils are made up of nucleotides, not lead. For the packet to be perfect, each colour has to compliment each other. For example, Aqua pencil (ie. Adenine) compliments Torquise (ie. Thymine) and therefore these colours can be placed side by side. Similarly, Cream (ie. Cytosine) and Grey (Guanine) are complimentary colours, and can too be placed next to each other. To execute the perfect drawing, (ie. a gene) we need to use ONLY complimentary coloured pencils. (eg. if we use aqua and torquise).

Most importantly, the colours we use (and their order) are vital to the end product. This example can be seen as a parallel to DNA, as the sequence of the bases is crucial to our genetic makeup.

LB

There are many factors that may effect the activity of an enzyme, one of them being the interference of an 'inhibitor'. There are two types of inhibitors: a competitive inhibitor and a non-competitive inhibitor. A __competitive inhibitor__ is one that physically blocks the active site of an enzyme, and prevents the substrate/s from bonding with the enzyme at its active site. A __non-competitive inhibitor__ is one that attaches to the enzyme, but NOT at the active site, and as a result causes a change in shape (temporary) of the active site, which consequently prevents normal bonding between the substrate/s and the enzyme's active site.
 * Effects on Enzymes - INHIBITORS:**

The production of a particular product may occur in several stages (a biochemical pathway), in which specific enzymes are used at the different stages. If an __inhibitor__ (eaither one)happens to interfere, at any stage of the biochemical pathway, then the continuous production of that specific product will be averted, (temporarily).

LA

Complimentary base paring

DNA is a nucleic acid made up of two strands each containing bases. There are four bases, adenine, thymine, guanine and cytosine. The two strands are joined by covalent bonds and only pair with a specific base. Cytosine and guanine are paired and adenine and thymine. This is called complimentary base paring.

MG

**Structures of enzymes** To create an enzyme, amino acids must go through phases in order to achieve its eventual 3D shape. The First stage/phase is called the primary stage. It is really this stage that is most important in Enzyme manufacture. This is due to the fact that this is the stage where amino acids are brought together to make long change, and if a wrong amino acid is brought it can affect the rest of the stages and the eventual shape of the enzyme. The next stage is called the Secondary stage. It is in this stage where the amino acid chain starts to take some shape by creating folds, pleats and helixes. This is caused by hydrogen bonds being formed between the different amino acids. The Tertiary stage is the third stage of enzyme production. It is here where the amino acid chains start to fold over on themselves and create a larger 3D shape; this is caused by interactions between the different R-groups. The last and final stage is called the Quaternary stage; this is where other amino acid chains in the tertiary stage join together to create and overall large 3D shaped enzyme. MW