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Deoxyribonucleic acid (DNA) is the precursor for nearly any living being that bears the genetic instructions. Its peculiar chemistry not only enables this knowledge to be replicated and passed on to descendants of an organism, but it also offers opportunities for scientists to analyze and manipulate an organism at a molecular level. Molecular biology methods are currently at the forefront of most cutting-edge scientific research. In this project, you will analyze a variety of widely used techniques involving DNA in molecular biology.
Molecular biology is a specialized branch of biochemistry, the study of molecular chemistry which is directly linked to living processes. The nucleic acids (DNA and RNA) and the proteins that are built using the genetic instructions contained in those molecules are of particular interest to molecular biology.
Other biomolecules, including carbohydrates and lipids, can also be analyzed for the interactions with nucleic acids and proteins they have. Molecular biology is often distinguished from the cell biology field, which focuses on cellular structures (organelles and the like), molecular mechanisms inside cells, and life cycles of cells.
The molecules that form the basis of life for scientists to research provide a more consistent and mechanistic method. Working with entire species (or even whole cells) can be unpredictable, with the outcomes of experiments depending on thousands of molecular pathways and external factors to deal with.
Molecular biology offers a toolkit for scientists, so they can “tinker” with the way life works. They could use them to determine the role of single genes or proteins, and decide what would happen if that gene or protein were absent or defective.
The following article includes some of the most widely used techniques in molecular biology-it is by no means exhaustive.
Electrophoresis-a mechanism that separates molecules such as DNA or proteins according to their size, electrophoresis is a foundation of laboratories for molecular biology. Although it may not sound like all that much knowledge to know the size of a molecule, it can be used to classify molecules or fragments of molecules and as a check to ensure we have the correct molecule present.
A mechanism used to amplify very small quantities of DNA to levels that can be used in additional experiments. It is used as a basic method in molecular biology to ensure that we have enough DNA to perform additional techniques such as genetic engineering but has broader practical applications such as forensics (identification using DNA profiling) and diagnosis of disease. PCR can also be used in a method called site-directed mutagens to introduce small point mutations into a gene.
The method of cutting DNA into smaller fragments using enzymes that work only on a specific genetic sequence.
The process of joining together two pieces of DNA. Ligation is useful when a new piece of DNA is inserted into another genome.
A method used during electrophoresis to precisely classify biomolecules. The molecule of interest is indicated by a labeled probe (a supplementary nucleic acid strand) or a labeled antibody raised against a particular protein.
The method of inserting a new gene into an organism or cell. This can be used to see what impact the gene’s expression has on the organism, to transform the organism into a factory that will generate vast amounts of the gene or protein for which it codes, or (within the presence of a label) to show where the gene’s products are expressed in the organism. Transformation is called injection of genetic material into a bacterium, while transfection is called injection into a eukaryotic cell. The process is called transduction if a virus is used to insert this material.
Each of these techniques, along with other techniques, is used to help scientists answer a specific research issue.
For example, after using PCR to produce large quantities of a specific gene, a scientist may connect a gene for a particular protein into a plasmid vector (a short circular DNA strand that acts as a carrier), perform a rapid digest and electrophoresis to ensure that the gene is properly inserted, and then use that plasmid to transform a bacterial cell that is used to prod After the vector is removed from the bacteria, it is then used in culture to transect a mammalian cell. The scientist then takes advantage of protein electrophoresis and western blotting to show the gene product expression.
Biological engines are one type of biological molecular machine; this is a biological molecule capable of translating chemical energy into motion and can be critical for biological functions such as muscle contraction, moving bacterial flagella, and ATP hydrolysis. These motors may either generate linear motions (muscle contraction, flagella movement) or rotary motions (ATP hydrolysis).
Examples of molecular biological machinery include myosin, kinesin, dynein, and ribosomes.
Myosin is a protein found in muscles that cause muscles to contract.
Kinesin is a protein transporting the “cargo” within the cell.
Dynein is a protein that forms part of motile cilia flagella and is responsible for the movement present in those proteins.
Ribosomes are an important part of protein synthesis, where the mRNA is converted into the appropriate polypeptide chain. During this step, the small subunit reads the mRNA, and the large subunit joins the corresponding amino acids to form the chain of polypeptides.
Biological molecular machines have one advantage of being capable of conducting complex functions. They aren’t incredibly healthy though, being biological. It is hoped that by learning how biological molecular machines function, others will be produced that can detect and track cancer cells or move inside the human body. Detect potential health problems.
Biological molecular machines were used as the basis for combining features of the said biological molecular machines with synthetic elements to form hybrid molecular machines.
In one study a light-actuated nano valve was made, consisting of a channel protein and spiropyrene, which is the active photochemical portion. This molecular hybrid system was used to monitor the movement of solutes over a lipid bilayer. UV light alters channel protein hydrophobicity, which then activates the channel. Visible light reverses this process, to close the door.
Completely synthetic molecular machines have also been developed, with the additional benefit of enhanced stability. These molecular synthetic machines can be broadly divided into seven different forms.
— Molecular motors; these rotate with an energy input in one direction. The energy can be of a light or chemical nature.
— Molecular propellers; these often rotate but, like a propeller, drive fluid around. Generally, these are made up of seven blades grouped around a shaft.
— Molecular switches; these are molecules that can exist in two equally stable forms, differing according to conditions such as pH, light, temperature, and electricity.
— Molecular shuttles; rotaxane belongs to this class and is designed using a macrocycle that threads a dumbbell-like molecule through. By moving the dumbbell-like molecule along the macrocycle this molecular machine will move ions from one position to another.
Molecular tweezers are molecules that can carry an object between its two arms in a cavity. Via hydrogen bonding, metal coordination, hydrophobic forces, van der Waals, and electrostatic forces, this is done.
— Molecular sensors; these molecular machines sense a specific analyte and then produce a measurable signal. For example, this may be used to detect metal ions and alterations in pH.
“Molecular logic gate;” these molecular machines need an input signal, which is typically chemical, and then generates an output signal. For example, a chromophore capable of responding to calcium ions shows a 390 nm absorbance, which is in the UV / visible range. Calcium addition causes a change in absorbance towards blue which decreases the absorbance. On the other hand, hydrogen induces a shift to red, which will then re-change the absorbance up to 390 nm.
Usually, biological molecular machines are driven by translating chemical, thermal, or light energy into kinetic energy. Perhaps this is the hydrolysis of ATP.
Any considerations need to be taken into account when it comes to synthetic molecular machines; for example, to build a rotary motor, it has to have 360 as much motion as it can regulate the direction and provide an energy supply. The task is to monitor the acceleration and the direction the molecular machine is going in. The asymmetric design typically gives better power, and a larger size is not generally correlated with improved performance.
These rotors can be shifted, either unidirectional or non-directionally, by Brownian motion.
These digital machines can be operated in different ways including H2O2 decomposition and the use of inert metal to generate an O2 gradient.
Since the function of a protein is determined by its three-dimensional structure, which is in turn determined by its sequence of amino acids, we will in effect know to potentially understand the role of each of the approximate 60,000-100,000 proteins encoded in the human genome and the roles of proteins in species that are essential to us, such as food crops and pathogens.
The goal would be to figure out which gene sequences have the greatest importance and usefulness in databases. As sequence data accumulation escalates, the key challenge facing researchers will move from the discovery of new genes and proteins to the discovery of the functions of genes and proteins whose sequence
Efficient recombinant DNA technology techniques are used in virtually every field of biological science. A debate about the future of recombinant DNA technology, therefore, amounts to contemplating the future of biological science in general. The most important recent influence of this technology is probably the sequencing of a variety of species’ entire genomes. As sequences of DNA are determined, they are deposited in public databases which are completely available to molecular cell biologists worldwide.
The genome sequences of additional multicellular model animals and plants are expected to be completed in the coming years.
The initial convergence of geneticists, physicists, and structural chemists on a popular problem provided an overview of the history of molecular biology: the essence of inheritance. Conceptual and analytical structures from each of these conceptual branches merged with the processes of gene replication, mutation, and expression in the ultimate determination of the double-helical structure of DNA (conceived as an explanatory molecule). With this recent history in mind, molecular biology theorists have discussed the field’s main concepts: mechanism, knowledge, and gene. Besides, molecular biology has presented cases in the philosophy of science to discuss more general problems such as reduction, interpretation, extrapolation, and experimentation.