Miller-Urey Experiment; Origin of Life

Miller-Urey Experiment; Origin of Life

The Miller and Urey experiment,  it was conducted in 1952 and published in 1953 by Stanley Miller and Harold Urey at the University of Chicago. It has been considered as a breakthrough  that made organic compounds out of inorganic ones by applying a form of energy. Their  idea was based on simulation of  hypothetical conditions on the early Earth as to test the biochemical origins of life.

Urey and Miller were testing the hypothesis of Alexander Oparin’s and J.B.S Haldane’s hypothesis, as they said that “conditions on the primitive earth favored chemical reactions that synthesized organic compounds from inorganic precursors.” This is consider to be classical experiment on the origin of life.

The reason that this experiment is consider a significant since after Miller’s death in 2007, scientists examined sealed vials preserved from the original experiments. They were able to show that there were well over 20 different amino acids produced in Miller’s original experiments. That is considerably more than those Miller originally reported, and more than the 20 that naturally occur in life.

Possibly one of the most important experiments was one conducted in 1952, when the scientists Urey and Miller, who were interested in the origin of life, and they carried out an experiment, to simulate an early Earth atmosphere. And you can see this rather ingenious apparatus where they’ve got some water boiling away inside a flask, being circulated into another container that’s got an electrical discharge apparatus. And this electrical discharge is discharging across an ancient simulated Earth atmosphere.
And they circulated this water round and round. And after a period of time, they found that the gases in this container, once they had been electrically sparked, transform themselves into amino acids, that we saw, are the building blocks of life. So, in this simple experiment, using only water and the constituents of early Earth atmosphere, these scientists managed to create the building blocks of life. This was a truly remarkable experiment, a breakthrough in astrobiology that allowed scientists to go from speculation about the origin of life, to thinking about how those early building blocks might well have formed. Nowadays we think that the atmosphere of early Earth is actually slightly different from the atmosphere that was used by Urey and Miller in the early experiments. But nevertheless this remains a remarkable and landmark experiment in the early history of Astrobiology, at least in the twentieth century. And taking our understanding of the origin of life to a new, empirical level.

 

References

[1] Hill H.G. & Nuth J.A. (2003). “The catalytic potential of cosmic dust: implications for prebiotic chemistry in the solar nebula and other protoplanetary systems”. Astrobiology 3 (2): 291–304. doi:10.1089/153110703769016389. PMID 14577878.

[2] Balm S.P; Hare J.P. & Kroto H.W. (1991). “The analysis of comet mass spectrometric data”. Space Science Reviews 56: 185–9. doi:10.1007/BF00178408.

[3] Miller, Stanley L. (1953). “Production of amino acids under possible primitive Earth conditions” (PDF). Science 117 (3046): 528. doi:10.1126/science.117.3046.528. PMID 13056598.

[4] Miller, Stanley L.; Harold C. Urey (1959). “Organic ccompound synthesis on the primitive Earth”. Science 130 (3370): 245. doi:10.1126/science.130.3370.245. PMID 13668555. Miller states that he made “A more complete analysis of the products” in the 1953 experiment, listing additional results.

[5] A. Lazcano, J.L. Bada (2004). “The 1953 Stanley L. Miller experiment: fifty years of prebiotic organic chemistry”. Origins of Life and Evolution of Biospheres 33 (3): 235–242. doi:10.1023/A:1024807125069. PMID 14515862.

[6] Bada, Jeffrey L. (2000). “Stanley Miller’s 70th Birthday”. Origins of life and evolution of the biosphere (Netherlands: Kluwer) 30: 107–12.

[7] BBC: The spark of life. TV documentary, BBC 4, 26 August 2009.

[8] “Right-handed amino acids were left behind”. New Scientist (2554). Reed Business Information Ltd. 2006-06-02. p. 18. Retrieved 2008-07-09.

[9] Brooks D.J. et al (2002). “Evolution of amino acid frequencies in proteins over deep time: inferred order of introduction of amino acids into the genetic code”. Molecular Biology and Evolution 19 (10): 1645–55. PMID 12270892

Molecular Dynamics: Bridge between Theory and Experiment !

Molecular Dynamics: Bridge between Theory and Experiment !

Molecular dynamics (MD) is a technique of computer simulation in which time evolution of large set of interacting atoms is followed by tracing their trajectory so that their corresponding equation of motion can be understood.  Molecular dynamics is becoming a celebrating technique which is now being used routinely, mostly in applied investigation of a wide range of dynamic properties and processes by researchers in numerous fields, including structural biochemistry, biophysics, molecular biology, pharmaceutical chemistry, and biotechnology. So the number of publications regarding MD theory and application of MD to biological systems is growing at an extraordinary pace. Using MD simulations, one is able to study thermodynamic properties and time-dependent (i.e., kinetic) phenomena of infinitely large complex structure of interacting atoms. Understanding the thermodynamics of the system one can develop various dynamic simulations using variety of algorithms in computer. In the simulation procedure, it has been considered the systems as small as an atom and a diatomic molecule undergoing a chemical reaction as large as a galaxy. Before doing MD simulation one needs to have knowledge of interaction potential for the particles, force due to these interactions, and the equation of motion that leads the particle dynamics. The interaction potential may vary with the mass and the distance between the interaction particles i.e the simple gravitational interaction between stars to the complex many-body forces between atoms and molecules. In conventional MD simulations, the energy function for non-bonded interactions tends to be a simple pair wise additive function (for computational reasons) of nuclear coordinates only. This use of a single nuclear coordinate to represent atoms is justified in terms of the Born-Oppenheimer approximation.The basic idea of molecular dynamics is the solution of the Newton’s law of motion in classical dynamics.

It has been noticed that the classical Newtonian equations of motion are adequate for many systems, including large biomolecules but for the systems with tunneling reactions, quantum corrections are important and need to include relativistic effects if we consider evolution of galaxy. In the MD simulation and its algorithm, it is supposed that the single particle motions as a function of time so they can be understood more easily than experiments to answer lots of properties of the system. To run the MD simulation, energy of the system is taken as a function of the atomic co-ordinates. We know, forces acting on the atoms of any system can be calculated by taking first derivative of the potential with respect to the atom positions. The force thus calculated gives dynamic behavior of the system by solving Newton’s equations of motion for the atoms as a function of time (M. Karplus, 1990). So, the major component in MD simulations is the force evaluation, specifically the long-range van der Waals and electrostatic interactions that must be computed for each pair of interacting components.

MD simulations are designed such a way that the result/simulation obtained is largely consistent with basic physical principles which can be validated by experiments. It is therefore, the Nobel Prize for Chemistry in 2013 [1] was awarded to Marin Karplus, Micheal Leavitt, and Arieh Warshall, who pioneered the MD simulations methodology for bimolecular systems. They explored that MD simulations evaluate the interactions between particles as a function of the coordinates of their individual substituent particles (e.g., atoms, residues/nucleotides, etc.). The foundation of MD is several theories from mathematics, physics, and chemistry, and it contains algorithms from computer science and information theory. The idea was originally conceived within theoretical physics but is applied today mostly in materials science and modeling of biomolecules. Before it became possible to simulate molecular dynamics with computers, some undertook the hard work of trying it with physical models such as macroscopic spheres.

Molecular dynamics is a specialized discipline of molecular modeling and computer simulation based on statistical mechanics; the main justification of the MD method is that statistical ensemble averages are equal to time averages of the system, known as the ergodic hypothesis. As stated by ergodic hypothesis, statistical ensemble averages are equal to time averages of the system if integration is performed to higher order. However, it is found that long MD simulations are mathematically limited because of cumulative errors in numerical integration of equations of motion. This error can be minimized with proper selection of algorithms and parameters, but cannot eliminate entirely. Furthermore, current potential functions are, in many cases, not sufficiently accurate to reproduce the dynamics of molecular systems, so researchers are taking use of computationally demanding Ab-Initio Molecular Dynamics method. Nevertheless, MD method allows detailed time and space resolution into representative behavior in phase space and thermodynamic properties of the large system.

It is found that there is a significant difference between the focus and methods used by various chemists and physicists while doing MD simulation and this is the key differences in the way used by the different fields. In chemistry and biophysics, the interaction between the particles is either described by a force field (classical MD), a quantum chemical model, or a mix between these two as a hybrid.

In applied mathematics and theoretical physics, molecular dynamics is considered as part of the research realm of dynamical systems i.e ergodic theory and statistical mechanics in general. So, theories of thermodynamics can be used to analyze the concepts of energy conservation and molecular entropy.

Some techniques to calculate conformational entropy such as principal components analysis come from information theory. Mathematical techniques such as the transfer operator become applicable when MD is seen as a Markov chain. Also, there is a large community of mathematicians working on volume preserving, symplectic integrators for more computationally efficient MD simulations. MD can also be seen as a special case of the discrete element method (DEM) in which the particles have spherical shape (e.g. with the size of their van der Waals radii.) Some authors in the DEM community employ the term MD rather loosely, even when their simulations do not model actual molecules.

 

References:

[1] The Nobel Prize in Chemistry. http://www.nobelprize.org, 2013.

[2] Gongpu Zhao, Juan R. Perilla, Ernest L. Yufenyuy, Xin Meng, Bo Chen, Jiying Ning,    Jinwoo Ahn, Angela M. Gronenborn, Klaus Schulten, Christopher Aiken, and Peijun Zhang. Mature HIV-1 capsid structure by cryo-electron microscopy and all-atom molecular dynamics. Nature, 497(7451):643–646, May 2013.

Image Copyright: Universität Stuttgart, IMWF

Chetanath Neupane: Journal Editor of {iaps}, 2019

Mr. Chetanath Neupane is a M.Sc. graduate of St. Xavier’s College (affiliated on Tribhuvan University, Nepal) and is currently working as an editor of {jIAPS}. He has a prior experience of working as a managing editor of his physics department publication called New Dimension for 2017 edition — he is very excited to work with people around the world !

Have a look: https://iaps.info/jiaps/what-is-jiaps/

He is continuously supporting {iaps} activities conducted by LC Kathmandu, Nepal. Unfolding his academic interests, he is highly motivated in the search for an answer to the question “are we alone in the universe?” To reach this answer, Chetanath studied Astrophysics (major) & Biophysics (non-credit), exploring the tiniest living organisms up to the largest object to date: the Universe. In order to give justice to this question, he is looking forward to doing a PhD in Astrobiology.

Chetanath has also been actively involved in scientific activities in Nepal for the last 10 years, and has participated and organized more than two dozen national & international conferences / seminars / workshops held in Nepal and abroad.

He has never been in ICPS –and is very eager to meet peoples working in IAPS in coming ICPS 2019 to be held in Germany !

Documentation for Visual Molecular Dynamics (VMD)

The VMD Installation Guide, User’s Guide, and Programmer’s Guide are available which describe how to install, use, and modify VMD.   All three guides are available from the main web site. Online help may be accessed via the “Help” menu in the main VMD window or by typing help in the VMD command window.  This will bring up the VMD quick help page in a browser, and will lead you to several other VMD help files and manuals.

Quick Installation Instructions


Detailed instructions for compiling VMD from source code can be found in the programmer’s guide.

 

The Windows version of VMD is distributed as a self-extracting archive, and should be entirely self-explanatory.

 

The native MacOS X version of VMD is packaged as a disk image and is extracted by opening the disk image, and dragging the “VMD” application contained inside into an appropriate directory.

 

 

For quick installation of the binary distribution for Unix do the following:

 

  • Uncompress and untar the distribution into a working directory, being sure to do this and subsequent steps as a non-root user. In this working directory, there are several subdirectories such as bin, src, doc, data, as well as this README and a configure script. Change to this working directory after the unpacking is complete.

 

  • Edit the file ‘configure’; change the values for the $install_library_dir and $install_bin_dir to a directory in which vmd data files and executables should be installed, be sure that you installing into a clean target directory and not overwriting an existing version of VMD (which would otherwise give problems):

 

  • $install_bin_dir is the location of the startup script ‘vmd’. It should be located in the path of users interested in running VMD.

 

  • $install_library_dir is the location of all other VMD files. This included the binary and helper scripts. It should not be in the path.

 

  • A Makefile must be generated based on these configuration variables by running “./configure”.

 

  • After configuration is complete, cd to the src directory, become root or use sudo if necessary, e.g., for installation of VMD into /usr/local or other permission-protected system directories and type “make install”.

 

  • This will install VMD in the two directories listed above. Note that running “make install” twice will print error messages because you are attempting to overwrite some read-only files.  Similarly, if you have incorrectly specified the target installation directories or attempt to overwrite an existing VMD installation, you will get error messages.

 

  • When installed, type ‘vmd’ to start (make sure the $install_bin_dir directory is in your path).

 

 

Required Libraries

——————

VMD requires several libraries and programs for several of its functions. In particular, it uses GL or OpenGL based 3-D rendering, and will require that you have the appropriate GL or OpenGL libraries on your system. Other programs are required by some of VMD’s optional features.

 

Please visit the VMD web site for more information: http://www.ks.uiuc.edu/Research/vmd/

NAAMII’s First Nepal Winter School in AI, 2018 to learn AI and machine learning fundamentals !

NAAMII’s First Nepal Winter School in AI, 2018 to learn AI and machine learning fundamentals !

<<< Register Here >>> https://nepalschool.naamii.com.np/register

Join NAAMII’s First Nepal Winter School in AI, 2018 to learn AI and machine learning fundamentals and get hands-on tutorials from world-class AI experts.

Application open for intensive 10 days AI school in Nepal with speakers coming from world-class research labs such as MIT, NYU, ETH Zurich, Imperial College London, King’s College London, University of Montreal and University of York.

AI is not just about using Deep Learning as a black box. AI Winter School offers lectures and lab sessions on mathematical fundamentals, computational neuroscience, graphical models, applications of ML in vision, medical imaging, language and panel discussions on future of AI and how AI is going to impact our society and our future.

AI Winter School aims to enrich and inspire AI professionals and empower them for new generation of AI leadership.

More details on the program on the website!
https://nepalschool.naamii.com.np/

Deadline for application: 25 Nov 2018 (now closed).
https://nepalschool.naamii.com.np/register

Dates: 20 Dec – 30 Dec 2018

Women are highly encouraged to apply!
We have a number of scholarships and travel grants available to students based on need and merit.

Organized by: NAAMII (NepAl Applied Mathematics and Informatics Institute for Research)

This event is powered by generous sponsorship from NCELL.

Surface ice at Moon’s poles

Surface ice at Moon’s poles

Water is the preliminary and fundamental requirement needed for everyday life. It is very unique molecule due to some important chemical properties, it has high surface tension and high value of specific heat capacity and more importantly, it is the only substance found on earth in its all three states, gas, liquid and solid.  Our planet Earth is blue planet and hence its greenery only because of presence of water in it. Earth is estimated to have approximately 1.4 x kg water in the oceans.  It is supposed that water is present over the entire universe since study reveals its presence in the interstellar medium (ISM) as well as in the spectra of stars.

 

Achieving the milestone of one of the great mission, a team of space scientists, led by Shuai Li of the University of Hawaii and Brown University & Richard Elphic from NASA’s Ames Research Center in California’s Silicon Vally, directly observed evidence of water in the form of ice on the moon’s surface which was found in the darkest and coldest parts of its polar regions. This is the very first evidence directly observed by the scientist supporting water on moon’s surface.

Image above clearly indicates the distribution of ice (blue colored locations) at the surface of moon, South Pole (left) and north pole (right). Observation has been detected by analyzing data from NASA’s Moon Mineralogy Mapper instrument called M3. M3, the Chandrayaan-1 spacecraft, launched by ISRO in 2008 significantly equipped to the confirmation of the solid ice presence on the moon. Data and direct observations have shown that the most of the ice is concentrated at lunar craters (Temperature < -250 F) at southern pole while the northern pole’s ice is more widely distributed.

Currently, a team of scientist is learning more about this ice, possible interaction with lunar environment as a key mission for NASA and commercial partners to learn our closest neighbor, Moon.

 

If you want to see the full paper published, follow the link-  Water on the surface of the Moon as seen by the Moon Mineralogy Mapper: Distribution, abundance, and origins

News source: NASA

Scientific analysis of Rudraksha seed !

Scientific analysis of Rudraksha seed !

Rudraksha is considered as a very sacred object in the Hindu Religion whose botanical or scientific name is Elaeocarpus Ganitrus Roxb.

Presently, 38 varieties of Rudraksha is recognized and cultivated in Nepal, Indonesia, Sri-Lanka, India and some other countries of south–east Asia.

According to the Hindu Mythology, ‘Rudra’ is other name of Lord Shiva and ‘Aksha’ means eyes or tears so rudraksha means tears of Lord Shiva. So, it considered to acquire very high cosmic force due to its link with eye of Lord Shiva in Hindu Mythology.  Roy (1993) found that Rudraksha beads possess inductive and electromagnetic properties and controls the human activities through direct action on central nervous system.

Botanically, Rudraksha seeds, or beads, are simply a plant product, containing wide range of elements like Aluminium, Chlorine, Copper, Cobalt, Nickel, Iron, Magnesium, Manganese, Phosphorus, Potassium, Sodium, Zinc, Silicon, Silver and Gold. Presence of these elements shows electromagnetic properties as well as high density value in Rudraksha seed.

Not only it contains ingredients of elements but also composed of some fraction of gaseous substances like Carbon, Nitrogen, Hydrogen and Oxygen. The percentage compositions of gaseous elements can be determined by C-H-N Analyzer and by Gas chromatography. The result obtained from above instruments was found as it consists of 50.031% carbon, 0.95% nitrogen, 17.897% hydrogen and 30.53% oxygen.

Human body can be assumed as a bio-electric circuit which contains billions of networks of nervous system and other organs which are sensitive to electrical impulses generated by continuous heart beats, blood circulation, sensory and motor impulses in nerves, contraction and relaxing of muscles. This electrical impulse generates bio-electricity inside the animal body which then produces some value of potential difference within body parts hence flow of this current is possible. But, sometimes, due to stress and other cause, this flow of bio-electric currents as well as normal body function stops working properly and we call this state as illness or abnormal psyche.

 

How Rudraksha helps in reduction of illness and regain bio-electricity flow inside the body?

 

1)  As I mention above, Rudraksha is a versatile material composed of wide range of valuable elements. Wearing Rudraksha obviously helps to control, normalize and more importantly, regulates the flow of bio-electric current inside the body.

If we talk about current then we should think of characteristic factors depending on it viz; resistance, capacitance, inductance, magnetic induction etc.

As we have the relation,

Ohm’s Law,

V= IR,   

Where, V= voltage, I= current, R= Resistance.

From above equation, resistance (R) generates some specific ampere of current flow depending on the factor of resistance.

If we correlate this concept in our case, resistance coordinated with our heartbeat and then specific impulses to the brain to generate certain bio-chemicals in the brain which brings positive mood, confidence and feel better and energetic.

 

2) We know capacitor is a device used to store an electric charge.

 

Let us impose this idea to our case again, Rudraksha can be considered as a capacitor in a sense that it can store bio-electric energy. As said above, bio-electricity flow depends on physical activity, stress, heart beats, hormonal activity, and nerve cell impulse, which gives larger value of potential difference as well.  Wearing Rudraksha seeds helps to regain normal body conditions by absorbing this excess bio-electricity.

 

 

3) Also, Rudraksha is inductor which sends out specific inductive vibrations because of its unique magnetic properties due to presence of magnetic materials.

   People wearing Rudraksha feels better even if beads do not touch them physically due to the vibrations.

4) Due to presence of variety  of elements, Rudraksha possess both paramagnetic and diamagnetic properties.

It can change its polarity called dynamic polarity due to diamagnetic property. As dia-magnetism is the ability of any substance to acquire temporary magnetic property in presence of an external magnetic field. The bio-electric flow in the body also develops bio-magnetism depending on the polarity of the induced magnetic field.

When Rudraksha comes in contact with our body it setup its polarity opposite to the inducing field. That is why it helps to proper functioning of the blood vessels better than magnets.

In one single line, Rudraksha can be considered as versatile material due to its composition as well as its use in numerous useful works.

 

Organic Molecules found in interstellar space !

Organic Molecules found in interstellar space !

Since historic times, we have wondered where we came from and where life originated. As it became apparent that the Earth was just one planet orbiting the Sun, that the Sun was just one star among ∼1011 in our galaxy, and that the Galaxy itself was only one such object among ∼1011 similar systems populating the Universe out to a cosmic horizon, with perhaps countless more lying beyond, it became clear that life on other planets, near some other star, in some other galaxy was possible. The cosmological principle also makes this idea philosophically attractive. It would suggest that life is some general state of matter that prevails throughout the Universe. The probability of finding some form of life, however primitive, on other planets either within the Solar System or around nearby stars seems very high from this point of view. Nevertheless, we are unable to predict where life should exist, mainly because we do not yet understand the thermodynamics of living organisms and what different forms life may take.

As we know, things to be in equilibrium they should follow some permitted rules. Likewise, thermodynamics distinguishes between three types of systems. Isolated systems exchange neither energy nor matter with their surroundings. Closed systems exchange energy but not matter, and open systems exchange both matter and energy with the surroundings. Biological systems are always open, but in carrying out some of their functions, they may act as closed systems. Biological processes also exhibit a well-defined time dependence. Some physical processes could take place equally well whether time runs forward or backward. If we viewed a film of a clock’s pendulum, we would not be sure whether the film was running forward or back. Only if the film also showed the ratchet mechanism that advances the hands of the clock, would we be able to tell whether it was running in the right direction. The pendulum motion is reversible but the action of a ratchet is an irreversible process. Biological processes are invariably irreversible. In an irreversible process, entropy, a measure of disorder, always increases. If a cool interstellar grain absorbs visible starlight and re-emits the radiation thermally it does so by giving off a large number of low-energy photons.

The Universe is fundamentally biological. Even the Urey-Miller experiment that simulated the theorized early pre-life conditions on Earth, and produced amino acids, suggests this. The ammonia used was obtained by a process involving hydrogen of bio-origin, and the methane was also biological in origin. Non-biological catalysts would be poisoned almost instantaneously by sulfur gases under pre-life conditions. What this means is that most of the material in interstellar grains must be organic or life itself would have been impossible. The spectrum for all grains along the line of sight from the galactic center to the Earth is very much like that of dry bacteria. Either the grains are bacteria or are organic grains in proportions like bacteria (amino acids, nucleic acids, lipids and polysaccharides). Therefore, both theoretically and observationally, organic constituents fit the observations. Organic materials or bacteria would easily align in magnetic fields, and could produce superconducting surfaces that would generate filaments. Organic materials or bacteria could more easily produce the variety of objects in the Universe than inorganic or non-biological materials. As with so much of its constituents, the Universe itself is fundamentally biological. In fact, so much is this the case that life constitutes a physical law; it had to arise, it was an inevitable complexity of the real world is even more extraordinary with a hierarchy of living things.

 

Life result of the laws of physics as they exist. Moreover, the evidence indicates that the variety and permeates all of space, it is built into the very substance of the Universe, and has even brought about its own self-consciousness we humans. Yet, we have done little, in the scientific realm, to ask one ‘open’ question: Why? And the reason is that most scientists are afraid to admit that the Universe is purposeful and fundamentally biological. If electromagnetism did not exist then there would be no atoms, no chemistry, no life, and no heat and light from the Sun. If there were no strong force then nuclei would not have formed, and therefore, nothing would be. Likewise, if the weak force and gravity did not exist, then you would not be reading this, nor would any form of life be here

Yet, these four very different forces (and no others), each vital to all of the complex structures that make up the Universe, are so fine-tuned that they all combine to make a single super-force. Granted that we do not specifically know how to search for exotic forms of life, could we not find indications of extraterrestrial life in a form familiar on Earth? All terrestrial living matter contains organic molecules of some complexity proteins and nucleic acids, for example and we might expect to find either traces of such molecules or at least of their decay products. We know of two quite distinct locations in which complex molecules are found. There may be many more. First, observations of interstellar molecules by means of their microwave spectra have revealed the existence of such organic molecules as hydrogen cyanide, methyl alcohol, formaldehyde, and formic acid. Larger molecules, such as the sugar glycol-  aldehyde, CH2OHCHO, have also been found to be quite prevalent in interstellar space. Infrared observations similarly have shown the existence of the even larger, polycyclic aromatic hydrocarbon molecules.

 

References:

[1] Choudhuri A. R, Astrophysics for Physicists, Cambridge University Press (2010)

[2] Gagnon, E. et al. Soft X-ray-driven femto-second molecular Dynamic.

 

S-S Bond in Proteins

S-S Bond in Proteins

Disulfide bond also known as S-S bond, or sometimes disulfide bridge. It is a covalent bond derived from two thiol groups. More importantly, these bonds observed to play an important role in protein stability and aggregation of large biomolecules.

SS bonds are formed by a thiol/disulfide exchange reaction, and three important factors are required in the reactive groups to form this bond: accessibility, proximity, and reactivity (electrostatic environment).

 

The most common way of creating this bond is by the oxidation of sulfhydryl groups. (2 RSH → RS-SR + 2 H+ + 2 e-) This process of oxidation can produce stable protein dimers, polymers, or complexes, in which the sulfide bonds can help in protein folding.

 

Disulfide bonds can occur two ways:

·         Intramolecularly – occurs within a polypeptide chain and are usually responsible for stabilizing tertiary structures of proteins.

·         Intermolecularly- occurs between polypeptide chains and are attributed to stabilizing quaternary protein structures.

 

 

 

 

 

Following Image credit goes to Wikipedia and Maria Monica Castellanos and Coray M. Colina of Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States

Some medications and its effect on Human Kidney (Renal System)

Some medications and its effect on Human Kidney (Renal System)

Several research findings reveals that some medications are harmful for Kidney function and responsible for Kidney stone formation.

 

“Medications that can damage the kidneys are known as “nephrotoxic medications.”

  • As we know whenever we go to the hospital having health issues, our treatment generally starts with antibiotic prescriptions. The problem arises when some of these antibiotics help to make crystals in renal system which don’t break down and blocks urinary track and hence urine flow.

 

  • Also, antibiotics constitutes some substances that can damage certain kidney cells when they try to filter them out. Some people also have allergic reactions to antibiotics that can affect their kidneys. All these things are more likely to happen if you take antibiotics for a long time or very high dose.

Vancomycin is an antibiotic used to treat severe  infections (methicillin-resistant Staphylococcus aureus (MRSA)) but research found  it cause kidney  damage and acute interstitial nephritis, or swelling in the kidney.”

     “Aminoglycoside Antibiotics are known for causing kidney injury (nephrotoxicity), even at low doses. People with chronic kidney disease, dehydration, or those who have been taking these antibiotics for a long time are at particularly high risk. The most toxic aminoglycoside is neomycin. Although these medications are typically intravenous and used in hospitals, they are important to keep at the back of your mind”

 

  • Water pills are used to treat high blood pressure and some kinds of swelling. They help our body get rid of extra fluid. But they can sometimes dehydrate or lowers the water level of our body, which can be bad for our kidneys.

  • Non-Steroidal Anti-Inflammatory Drugs (NSAIDs)  like aspirin, ibuprofen, or naproxen  shouldn’t use them regularly for a long time or take high doses of them.

  • Some medications like omeprazole, Aciphex, Prilosec, Prevacid, Nexium are used to treat heartburn, ulcers, and acid reflux also called Proton Pump Inhibitors (PPIs).These drugs principally works by blocking the secretion of gastric acid. Although these powerful acid blockers were never designed for long-term use but unfortunately millions of peoples around the globe take these drugs indefinitely which potentially cause deadly consequences They lower the amount of acid in our stomach, but recent studies have shown that taking them for a long time can raise our chances of serious kidney problems and possibly lead to kidney failure. Researcher suggested that If you take a PPI regularly, ask your doctor about the possibility of switching to another drug which might  be far better for your health .Now, a new study from Stanford University shows these drugs double the risk of dying from a heart attack or stroke.

  • Some supplements like creatine and wormwood oil, may bad for our kidneys. It is recommended to tell your doctor about every supplement you take to make sure they’re helping or leading to damage of your body organ.