Nicolle A. Rosa MercadoBIOL 4997Importance and Pipetting PracticeIn this laboratory we reviewed pipetting concepts. We did large and small volume exercises with afocus on micro-pipets. Concepts, such as the uses of the first and second stops, were discussed. It isvery important to keep these concepts fresh due to the fact that they are the most practicedlaboratory techniques. Pipetting is the key to any experiment because, if the amount measured is notprecise or if the pipet is contaminated with another substance, everything might go wrong. Theexercises were verified based on the color obtained at the end. The amount was verified by (settingthe micro-pipettes to the total amount of substances that were placed in the tube to ensure that theamounts were measures accurately.Microscopy and PhotomicrographyDuring this laboratory, microscopy and micro-techniques were reviewed. It is of uttermostimportance for every scientist to know how to work with a microscope. Microscopes provide greatevidence of discoveries that have been made. They are also very helpful for studying differentmicroscopic organisms, such as bacteria. Here we reviewed the uses of different parts of themicroscope. We also learned how to take pictures using QCapture. The class was divided into fourgroups and each learned a different micro-technique. Each individual was assigned to teach anotherstudent how to use the technique he had learned. My task consisted of learning how to use afluorescence microscope to teach the technique to one of my colleagues. I was taught how to use thephase-contrast microscope. In conclusion, each student learned how to work with two differentmicro-techniques and reviewed the uses of the microscope’s parts.Workshop UNC - From DNA to ProteinIn this three day laboratory experience we were taught several genomics and proteomics techniques.We reviewed techniques such as agarose gel electrophoresis and SDS-PAGE. The first day of theworkshop we were taught how to extract our own DNA using easy-to-find products. During thesecond day, we ran a PCR and read the results through agarose gel electrophoresis. Therepresentatives of the University of North Carolina at Chapel Hill also helped us review the centraldogma of biology and how these procedures work. The third day we spoke about proteins and theirimportance in lysosomal storage disorders. We discussed how to prepare SDS-PAGE, WesternBlots, and Coomassie stains. These techniques are very common laboratory tools. They are veryimportant in biology and, specifically, in genetics because they help scientists to differentiate genesand proteins due to characteristics, such as their size, that can only be observed by using these tools.A person who knows how to do these techniques has a great advantage in the scientific community.Nanotechnology and Electron MicroscopyDuring this seminar offered by Dr. Wilfredo Otaño, we discussed concepts regarding nanoparticlesand electron microscopy. This experience helped us review the many applications that nanoparticleshave on biomedical research. One of the most important advantages provided by nanoparticles isthat they provide more surface area. Here we were taught procedures such as electrospinning. Thisprocess is powered by an electrical charge that pulls a liquid added to a syringe and placed within
the device. This produces fibers that will contain whatever substance was added to the syringe. Thefibers are then submitted to a process called sputtering in which they are transformed into a metallicstate. After this process is completed, the fibers may be observed under an electron microscope. Dr.Otaño also showed us around the physics laboratory and told us about the research that is beingdeveloped within his lab. He explained the uses of all of the different machines within thelaboratory. Some of them were made by students that work in this laboratory.Column Chromatography and SDS-PageThrough this seminar, Dr. V. Bansal reviewed protein concepts with the group. She emphasized theimportance of protein isolation and how this is made possible. Proteins can be isolated usingmagnetic nanoparticles. These are used because they posses certain characteristics that make themeasier to work with in this field of research. For the isolation to be possible, certain steps arerequired. These steps include precipitation techniques, filtration methods, centrifugation, andchromatography. These concepts are important because their results may be used as catalysts,therapeutics, or dietary supplements. After the proteins were isolated, following the procedureslisted in the handouts, each group had to prepare a SDS-PAGE. This last step was necessary in orderfor us to know if we had isolated the correct protein. The SDS-PAGE gels were prepared during theweek in the RISE laboratory with the technician’s help. The results from my group were positivedue to the fact that it showed a band representing the first wash. This indicates that the protein wasappropriately isolated because the non-specifically bound proteins were removed.Protein Interactions: an In silico approachDuring the seminar Dr. Maldonado spoke about the different processes a prescription drug has to gothrough before it may be prescribed. He taught us about structure based drug design,pharmacophore models, and drug discovery strategies . In the hands-on part of this seminar we weredivided into four groups in order to complete four different tasks. The tasks were to identify optimaltargets for drug development (benzene mapping), to do pharmacophore identification and modelgeneration, primary screening, and secondary screening. My group was assigned the last step whichwas secondary screening, or docking screening. In order to complete our task we used the NXClient Application. Here we transfer a series of files from the computer to the application.Afterwards we opened the file in CyberDuck, downloaded the file from NanoBio, and opened theresults in Excel. We sorted the compounds by affinity and selected the best five. Later we analyzedthe chosen substances using PyMol. Here we were able to take pictures of the compounds. The
topic of this seminar has a major importance in the biomedical field because it helps us predict howeffective a drug may be. It also helps us have a better understanding of how drugs work.Phages & ProteomicsThis seminar presented by Dr. Rubin consisted of two seminars. He spoke aboutmycobacteriophages, which are viruses that infect bacteria that belong to the genusMycobacterium, and about proteomics. Proteomics is the study of protein functions and it is ofgreat help in this type of research. Dr. Rubin also discussed the importance of aseptic techniquesduring research. During the practical part of the seminar, which lasted most of this semester, theclass was divided into pairs. We each had to bring a soil sample in which we had to look for phagesfollowing the protocols provided by the professor. As soon as each group had at least one phage,we had to do plaque screening and plaque purifications. Once my partner isolated some phages, sheprepared phage filtrates. After the proteomics conference that Dr. Rubin gave us, we analyzedthem. By using SDS-PAGE, we were able to determine the size of the two new phages. We alsohad to prepare a progress report in which we had to present all the information regarding ourphages and the protocols that had been completed so far. This research is of great importancebecause it provides a possible solution for diseases caused by antibiotic resistant bacteria.Water sampling, testing, and statistical applicationDuring this seminar, Dr. J. Arce spoke about the different factors affecting water quality and thedifferent techniques available to determine it. This workshop included an individual activity thatconsisted of collecting a water sample from anywhere you could and testing it for total and fecalcoliforms. The sample should have been collected within a maximum of six hours before beginningthe protocol. After the sample was collected, ONPG and MUG enzymes were to be added. Theseenzymes are able to identify total and fecal coliforms that may be present in the sample. Thesample had to be incubated for a period of twenty-four hours at thirty-five degrees Celsius. If thesample presented a yellow color and had green spots when exposed to ultra violet radiation itcontained total and fecal coliforms and should not be considered drinkable. My sample did notcontain total or fecal coliforms. It was taken from a faucet in Cayey, Puerto Rico. The scientificimportance of this type of investigation is that it allows us to determine what water can beconsumed without being dangerous to our health. It also tells us if the water purification protocolsbeing used are providing effective results.