Phosphorylation: New and Improved Ways

This article talks about new ways to detect phosphorylation. First off, what is phosphorylation? It is the addition of a phosphate (PO43-) group to a protein or other organic molecule. Phosphorylation plays a significant role in a wide range of cellular processes. After years of research, scientists now know that the presence of a phosphate molecule (usually attached to threonine, serine, and tyrosine residues) can show the difference between health and disease. Protein kinases transfer phosphate groups from ATP to the serine, threonine, or tyrosine residues on protein peptide substrates, which directly affects the activity and function of the target. Through time, research has revealed how cells respond to insulin, and how cancer can develop when there is a mishap in phosphorylation. Other discoveries are showing that phosphorylation could be involved in mood disorders, diabetes, and Alzheimer’s disease.

Studying phosphorylated proteins is always a challenge. Nowadays, a popular method in viewing these proteins is the use of antibodies that specifically bind phosphorylated proteins. The availability of phospho-specific antibodies has opened the door for the improvement of traditional methods as well as the development of new immunoassay techniques. These antibodies can be used as investigation to detect phosphorylated proteins on a Western blot (adaptation of the Southern blot procedure, used to identify specific amino-acid sequences in proteins). The Western blot is the most common method used for assessing the phosphorylation state of a protein.

Assessing protein phosphorylation is often an essential component of the biologist's collection for understanding intracellular factors underlying cellular activities. Given the important role kinases play, it is critical for researchers to have quality tools for measuring protein phosphorylation. Each technique excels in different contexts, and scientists should have the knowledge to choose the method that best fits the experimental design.

Article:

Improved Ways to Detect Phosphorylation

DNP: Weight Loss Drug Caused Deaths

This article explains the pros and cons of DNP (2,4-Dinitrophenol). DNP is a potent chemical promoted as a weight loss drug because it speeds up fat metabolism. While DNP significantly enhances your weight loss efforts, this drug can be toxic to humans, and its use has already resulted in death.

DNP was first used as a weight loss drug in the 1920s. As a result, DNP became a popular weight loss drug and was used until 1938, when it was banned by the Food and Drug Administration (FDA) due to the number of toxic effects and deaths associated with its use.

How exactly does DNP help aid in weight loss? The way that this drug works is that it greatly increases the rate your metabolism. This is because it interferes with your body's ability to produce ATP (adenosine triphosphate), which provides energy for your body. When this deficiency occurs, your body must increase its metabolic rate and burn more fat to meet energy demands. This results in excessive weight and fat loss over a short time.

However, the side effects included increased heart and breathing rates, along with increase of body temperature. This is due to the large amount of heat that is produced during the DNP's interference with the body's ATP production. In severe cases, DNP can cause rapid heart and respiration rate, kidney failure, and may also lead to death.

(The image above shows the chemical structure of 2,4-Dinitrophenol)

Article:

DNP and Weight Loss

Chapter 7: Useful Materials

This video gives a complete overview of glycolysis. He breaks down the process of glycolysis and explains the steps involved in this process. Glycolysis is part of cellular respiration, which also consists of two other parts called the Krebs Cycle (Citric Acid Cycle) and the electron transport chain. This video mainly focuses on glycolysis, which is the break down of glucose. He explains how there are two main stages of glycolysis; which can be called the investment phase (which uses 2 ATPs to break down glucose into two 3-carbon compounds with a phosphate attached) and the pay-off phase (when each of the phosphate attached to the carbon turns into pyruvate, which is essentially the end product of glycolysis - for every one molecule of glucose there are 2 molecules of pyruvate). I thought this video was very helpful in reviewing the process of glycolysis.

I found an animation of the Krebs Cycle (Click Here) online. It explains the Krebs Cycle and each individual step involved in this process. The Krebs Cycle begins after the two molecules of the three carbon sugar produced in glycolysis are converted to a compound called acetyl CoA. At the end of the animation there is a review, where you have to place each step of the Krebs Cycle in the correct order.

What Are Ribozymes?

First off, what is a ribozyme? Well ribozymes are RNA molecules that are able to catalyze chemical reactions. Up until the 1980s, scientists thought all biological catalysts were proteins. But then it was discovered that some RNA molecules can act as enzymes; meaning that they can catalyze covalent changes in the structure of substrates. However, since their discovery there has been intense research in learning about the structure and activity of ribozymes.

(The image above is the crystal structure of a full-length hammerhead ribozyme. Image A is a schematic diagram, while image B is a ribbon diagram.)

Among RNA molecules, the large ribozymes, mainly groups I and II introns (nucleotide sequence within a gene that is removed by RNA splicing to generate the final mature RNA product of a gene) and RNase P (ribonuclease P, which is a catalyst found in bacterium), are of special importance. Why? Well these three groups of ribozymes show a significant requirement for metal ions in order to establish the active tertiary structure that enables catalysis. The primary role of metal ions to screen the negative charge associated with the phosphate sugar backbone.

Article:

Multiple roles of metal ions in large ribozymes.

Drug Improving Metabolism!

A new asthma drug, formoterol, showed significant ways to improve fat and protein metabolism. Formoterol is a synthetic catecholamine (hormone that regulates heart rate, metabolism and breathing), the metabolic effects have not previously been studied in people. However, therapy doses given to animals have shown that it stimulates metabolism without affecting the heart.

This was proved by a team of Australian researchers, including team leader, endocrinologist Dr Paul Lee. According to Lee, "formoterol is a new generation of this class of medication. It is highly selective for the kind of catecholamine receptors found in the lungs, and not those in the heart. The new drug is also more selective for a similar receptor found in muscle and fat. In theory at least, it should have beneficial metabolic effects -- like the older class of medication -- without affecting the heart." In an experimental test, formoterol was given to eight healthy men over the span of one week. Within that week their energy metabolism increased over 10%, fat burning increased over 25%, and protein burning decreased by 15%. Therefore, these men burned fat while reducing the burning of protein. These results are beneficial because over a period of time, such effects can lead to a loss in fat mass but an increase in muscle.

Article:

New Generation Asthma Drug Could Improve Metabolism, Research Suggests

A Violation in the 2nd Law of Thermodynamics?

This article basically explains how the second law of thermodynamics does not make sense when systems get sufficiently small. The second law of thermodynamics states that the transfer of energy or transformation of energy form one form to another increases the entropy (degree of disorder). A perfect example of the second law of thermodynamics: a hot frying pan cools down when it is taken off the kitchen stove. Its thermal energy ("heat") flows out to the cooler room air; the frying pan cannot heat up again without adding energy. Scientists prediction about how the second law of thermodynamics may not always be accurate occurred nearly a decade ago; their prediction stated that small assemblages of molecules inside larger systems may not always tolerate this law.

From the Australian National University, Genmiao M. Wang and his colleagues discovered the inconsistency of such law when they dragged a micron-sized bead through a container of water using optical tweezers. They found that, sometimes the water molecules interacted with the bead in a way that energy was transferred from the liquid to the bead. This occurred by using the random thermal motion of the water to do the work of moving the bead. According to these researchers, if such movement lasted less than two seconds, the bead would most likely be able to gain energy from the water as it was to add energy to the reservoir. These findings suggest that the function of machines may have basic limitations.

Article:

Second Law of Thermodynamics Violated

Nobel Prize: Chemistry

The Nobel Peace Prize in Chemistry was awarded to Israeli scientist, Dan Shechtman on October 5, 2011. Daniel Shechtman won for the discovery of quasicrystals. Most crystals are composed of a three-dimensional arrangement of atoms that repeat in an orderly pattern. Depending on their chemical composition, they have different symmetries. But quasicrystals behave differently than other crystals. They have an orderly pattern that includes pentagons, fivefold shapes, but unlike other crystals, the pattern never repeats itself exactly.

(This picture displays Israeli scientist, Daniel Shechtman, sits next to a transmission electron microscope at the Haifa Technion Institute of Technology in Israel on Wednesday.)

The existence of quasicrystals, though controversial, was anticipated much earlier, but Shechtman was the first to see them in nature. Shechtman first saw the startling image on April 8, 1982, while studying a rapidly chilled molten mixture of aluminum and manganese under an electron microscope. What he saw appeared to counter the laws of nature.

The finding was more than just theoretical. Quasicrystals have been used in surgical instruments, LED lights and non stick frying pans. They have poor heat conductivity, which makes them good insulators.

(The image above is an atomic model of a silver aluminum (AgAl) quasicrystal)

Article:

What are Quasicrystals, and What Makes Them Nobel-Worthy?

Hold Your Wee for a Wii!

In 2007, Jennifer Strange died after competing in a radio station contest. The contest was held to see how much water you could drink without going to the bathroom; the prize was a Nintendo Wii video game system. Jennifer supposedly drank 2 gallons (7.5 liters) of water over approximately two hours.

What caused Jennifer Strange's death? Well she died due to water intoxication, which is caused by drinking too much water and can also cause hyponatremia (dilution of sodium in the body). When too much water enters the body's cells, the tissues swell with the excess fluid. The cells in our body maintain a specific concentration gradient, so excess water outside the cells (the serum) draws sodium from within the cells out into the serum in an attempt to re-establish the necessary concentration. As more water accumulates, the serum sodium concentration drops (hyponatremia). The other way cells try to regain the electrolyte balance is for water outside the cells to rush into the cells via osmosis. Osmosis is the movement of water across a semipermeable membrane from higher to lower concentration. Both electrolytes and water move across the cell membrane in an effort to balance concentration.

Therefore, Jennifer Strange died not specifically from the amount of water she drank but how fast she drank that water. You are unlikely to suffer from water intoxication, even if you drink a lot of water. As long as you drink over time as opposed to intaking an enormous volume all at once.

Article:

Woman dies after water-drinking contest