Evolution favors protein mutational robustness in sufficiently large populations

BACKGROUND: An important question is whether evolution favors properties such as mutational robustness or evolvability that do not directly benefit any individual, but can influence the course of future evolution. Functionally similar proteins can differ substantially in their robustness to mutations and capacity to evolve new functions, but it has remained unclear whether any of these differences might be due to evolutionary selection for these properties. RESULTS: Here we use laboratory experiments to demonstrate that evolution favors protein mutational robustness if the evolving population is sufficiently large. We neutrally evolve cytochrome P450 proteins under identical selection pressures and mutation rates in populations of different sizes, and show that proteins from the larger and thus more polymorphic population tend towards higher mutational robustness. Proteins from the larger population also evolve greater stability, a biophysical property that is known to enhance both mutational robustness and evolvability. The excess mutational robustness and stability is well described by existing mathematical theories, and can be quantitatively related to the way that the proteins occupy their neutral network. CONCLUSIONS: Our work is the first experimental demonstration of the general tendency of evolution to favor mutational robustness and protein stability in highly polymorphic populations. We suggest that this phenomenon may contribute to the mutational robustness and evolvability of viruses and bacteria that exist in large populations

Exploration of Pyriform Spidroin1 (PySp1) QEA Module’s Role in Fiber Formation and Properties

Spider silk, known for its tensile strength, extensibility and toughness, has a wide array of potential uses that span from medical equipment to military armor. Spider silk’s strength is comparable to high-tensile steel, yet it can withstand considerable strain or extensibility without breaking. There are several types of spider silk, each originating from a different silk- producing gland. These fibers provide different functions for spiders, ranging from web constructions to locomotion. Pyriform spidroin 1 (PySp1), the protein under study, was first identified in the pyriform gland, whose main function is to produce silk that is used to immobilize dragline silk. Our research focused on the significance of PySp1 QEA module and its relationship to the mechanical adhesive properties of pyriform silks. The PySp1 cDNA encoding the QEA module was amplified from a cDNA library prepared from the silk-producing glands of the black widow spider, Lactrodectus hesperus. After insertion of the cDNA into a prokaryotic expression vector, we transformed E. coli and performed a restriction digestion analysis to check for the cDNA insert presence and correct directionality. Following the validation of the presence of a cDNA insert, the QEA PySp1 cDNA was induced and its product monitored through both blue silver staining and western blotting. Western blot analysis showed that QEA PySp1 was expressed in high levels. To further understand its role in pyriform silk formation and function, we plan to purify the protein through nickel affinity chromatography. We hope to spin fibers from the purified protein solution in order to better comprehend its mechanical properties and function

Exploration of Pyriform Spidroin1 (PySp1) QEA Module’s Role in Fiber Formation and Properties

Spider silk, known for its tensile strength, extensibility and toughness, has a wide array of potential uses that span from medical equipment to military armor. Spider silk’s strength is comparable to high-tensile steel, yet it can withstand considerable strain or extensibility without breaking. There are several types of spider silk, each originating from a different silk- producing gland. These fibers provide different functions for spiders, ranging from web constructions to locomotion. Pyriform spidroin 1 (PySp1), the protein under study, was first identified in the pyriform gland, whose main function is to produce silk that is used to immobilize dragline silk. Our research focused on the significance of PySp1 QEA module and its relationship to the mechanical adhesive properties of pyriform silks. The PySp1 cDNA encoding the QEA module was amplified from a cDNA library prepared from the silk-producing glands of the black widow spider, Lactrodectus hesperus. After insertion of the cDNA into a prokaryotic expression vector, we transformed E. coli and performed a restriction digestion analysis to check for the cDNA insert presence and correct directionality. Following the validation of the presence of a cDNA insert, the QEA PySp1 cDNA was induced and its product monitored through both blue silver staining and western blotting. Western blot analysis showed that QEA PySp1 was expressed in high levels. To further understand its role in pyriform silk formation and function, we plan to purify the protein through nickel affinity chromatography. We hope to spin fibers from the purified protein solution in order to better comprehend its mechanical properties and function

A system study on White Horse Plastic Manufacturing

A system study was conducted on White Horse Plastic Manufacturing, a company that produce plastic films and bags like LDPE, HDPE, and PP. Currently, the company has three locotions located in Malabon City but the study will only focus on only one location which is the main plant. The study would be focusing on the production operations, warehousing and delivery system or the company\u27s row materials and finished goods. The study would cover the entire manufacturing operations of the compony which includes the delivery of raw materials to the production operations until the delivery of the finished products to the customer. Based on the findings in the present system and comparing it with the objectives of the company, the company was evaluated by determining their strengths, weaknesses, opportunities and threats. Upon conducting SWOT and WOT-SURO Analysis, it was determined that the biggest problem of White Horse Plastic Manufacturing is the amount of returns of the company which is composed of 2.03% of all bundles shipped in 2018 deviating from the tolerable rote of 0% that led to an opportunity cost of P795, 142 and on actual cost of Pl ,222,405.49. This problem was further analyzed by using a Why-Why Diagram, interviews with the management and workers of the company, time study, and Pareto Chart Analysis to determine the root causes of the problem. It has been found that there ore 6 root causes, namely: socks containing different sizes look identical, size delivered was not checked prior to delivery, plastic size did not pass the customer\u27s standard, plastic gels caught on protruding objects when transported to the designated area resulting to holes, thickness of the plastic did not pass the customer\u27s standard, and temperature of the machine does not reflect the setting it was placed on. After identifying all the 6 root causes, solutions were then generated to address these root causes. The solutions generated were assessed through the Kepner Tregoe Decision Analysis and were also backed up with simulation and real-life changes. The solutions proposed for each root cause are the following: Sacks containing different sizes look identical. -Assign color coding and fixed places for each size in the warehouse The size delivered was not checked prior to delivery. -Implement the poka yoke system in the transportation process of the finished goods The plastic size did not pass the customer\u27s standard. -Match tolerance levels in the quality checking of the length and width Plastic gets caught on protruding objects when transported to the designated area resulting to holes. -Implement 7S methodology in the finished goods warehouse and loading area. The thickness of the plastic did not pass the customer\u27s standard. -Match tolerance levels for the quality checking of the thickness The temperature of the cutting machine does not reflect the setting it was placed on. -Automated the production process for the cutting machine The proposed system was validated through the Vensim software and doing it in real-life. Toe implementation plan of this proposed system took 23 days in total. Moreover, implementing the proposed system will cost P48 I ,435.72 which was solved by applying the Cost Benefit Analysis. The total benefit will amount to Pl,255,903.68 and the net benefit will amount to P774,467.96

The impact of foreign ownership on stock price return volatility of the financial, industrial, holding firms, property, service, mining & oil industry for the years 2008-2012

The paper aims to assess the impact of foreign ownership on stock return volatility of the firms listed in the Philippine Stock Exchange (PSE) for years 2008 to 2012. Using a panel data random effect model (REM) regression, the researchers identify which among the six industries (financial, industrial, holding firms, property, service, mining & oil) in the market has the most and least stabilization effect on stock return volatility. Amid global disruption, the improving performance of the country\u27s economy, which is reflected on the stock market, attract foreign investors. It is however, a question whether these participants would want to take profit by having short-term or long-term investments. The researchers find that, on aggregate, foreign investors has a direct relationship on the volatility of stock returns implying their speculative characteristics and increased exposure of the domestic market to world market information. Finally, it is conlcuded in this study that the financial industry is least stabilized while property industry is almost stabilized