2,087 research outputs found
Mechanistic behaviour and molecular interactions of heat shock protein 47 (HSP47)
This project involves the study of heat shock protein 47 (HSP47), which is a molecular chaperone crucial for collagen biosynthesis. It exhibits a high degree of sequence homology with members of the serine protease inhibitor (serpin) superfamily, though HSP47 does not possess the inhibitory activity. It is a single-substrate chaperone, and binds only to collagen. ‘Knock-out’ of the hsp47 gene impairs the secretion of correctly folded collagen triple helix molecules leading to embryonic lethality in mice. Thus the aim of this project was to elucidate the specific mechanism that governs the binding to and release from collagen at the molecular level, known as the ‘pH-switch mechanism’. Emphasis is given on histidine (His) residues as the HSP47-collagen dissociation pH is similar to the pKa of the imidazole side chain of His residues. Site directed mutagenesis was used to mutate surface His residues, based on a mouse HSP47 homology model. The effects of the mutations on the behaviour of HSP47 were then assessed by collagen binding assays and structural analyses with circular dichroism (CD). All mutants were found to have good solubility and retain their binding ability to collagen like wild-type HSP47 in batch assay, but perturbed behaviour was seen in column experiment. Mutation of His residue at position 191 (H191) causes the shift in the collagen dissociation pH, while mutation of H197 and/or 198 disrupt the specific HSP47-collagen interaction. H191, 197 and 198 are predicted to be located in the region near the C-terminus of strand 3 of β-sheet A (s3A) in the homology model, a region specifically known as the ‘breach cluster’ in serpin nomenclature. The extent of conformational rearrangement of this region was further investigated by means of intrinsic tryptophan fluorescence spectroscopy using a series of single tryptophan (Trp) mutants. Results from analyses performed on the mutants did not contradict the observation seen in His mutational work, as Trp residues in the ‘breach’ cluster are likely to be located in the dynamic region of HSP47 pH-triggered conformational change. In conclusion, this study establishes the importance of His residues in the ‘breach cluster’ to HSP47 pH-switch behaviour. Finally, a model for HSP47 pH-switch mechanism was proposed from data obtained via mutagenesis experiments. The model is hoped to assist future research into HSP47 cellular behaviour and will also be of great use in therapeutic applications involving the molecular chaperone
Bioinformatics tools @ NBBNet: online infrastructure for the management and analysis of biological data
The use of informatics tools for the management and analysis of sequences for nucleic acids and proteins has resulted better throughout capability of wet lab research work to infer biological data to functional biological information. The field of computational biological information management and analysis is generally known as bioinformatics. We discuss some tools and processes which have been developed or integrated into a data management and information presentation pipeline by the Malaysian National
Biotechnology and Bioinformatics Network. Central to this is the Bioinformatics Tools @ NBBnet online infrastructure system. This infrastructure system utilizes grid computing technology. In addition, the deployment of niche databases and database shells for research applying specific datasets
such as a particular protein function, protein family or genomes have been
discussed
City Bus Characteristics : Ipoh- Tanjung Rambutan
This study evaluating public bus transportation operated along Ipoh - Tanjung
Rambutan route. Service evaluated in term of frequency, time and route. Collecting data
in identifying passengers and residents characteristics for demand level analysis. Data
collected by survey and observation at study area. Survey form distributed randomly to
passengers and residents. Characteristics extracted from survey organized into
presentable form for demand analysis use. Bus service provided evaluated by Urban Bus
Design. Actual data on site compared to results defined by Urban Bus Design. From the
survey done, 51% are below 25 years old using public bus for transportation purpose.
Most of them are students whose use public bus as mod of transportation from home to
school and vice versa. Majority of passenger (61%) are with low income below RM500
per month. They are combination of students and factory workers. By survey of
frequency on using bus per week, 39% of residents is not using bus at all and prefer to
use own transportation like cars and motorcycle. Performance of bus operations is
compare to Urban Bus Design method. As the results, number of buses provide for the
service is not adequate for current amount of passengers ride per hour. Four buses
provided but the service should provide seven buses to accommodate the passengers.
These causes produce long waiting time for passenger with 26 minutes. Few numbers of
bus stops within residential area make its more difficult for residents to use public bus.
From survey, 67% have to walk more than 5 minutes to reach the nearest bus stops. Ipoh
City Council (Majlis Bandaraya Ipoh) in their Ipoh Structure Plan (1998 - 2020)
promising Ipoh local in improving city public transportation by building infrastructure of
integration terminal center in Meru Jaya and South Chemor. Several recommendations
has been made for improvement of public bus Ipoh - Tanjung Rambutan routes.
Increasing number of bus stops and adding up one more bus for operations is some of the
recommendations
Quality of education in UiTM Kedah: Bachelor of Administrative Science students’ perspectives / Mohd Firdaus Yusoff and Mohd Firdaus Osman
The purpose of this study is to analyze the quality of education focus on students’ performance (CGPA) in UiTM Kedah from the Bachelor of Administrative Science students’ perspectives based on the requirement of ISO 9001: 2000 and quality objective in UiTM Kedah . Among the factors that contribute to the quality of education in higher education are facilities, lecturers and student readiness and this study aimed to find out the relationship between the three factors with the quality of education (CGPA). The population of the study is all the students from Bachelor of Administrative Science in UiTM Kedah except part one, two and three student due to still new and not familiar with lecturers and infrastructure provided. The total of 163 students will be represented as the sample size of the study from the all number of populations (census). The research will be taken place one semester from January 2010 until April 2010
Automatic System For Utility Electrical Fault (Fault Location Detection Using Labview)
Software called LabVIEW is used to develop the system that can detect the location of permanent fault in a domestic electrical wiring system. The idea is when the location of fault is determined, an automatic system to isolate the Miniature Circuit Breaker (MCB) that has fault can be eveloped. So when the MCB that has fault has been isolated, the ELCB can be turned on without tripping again
Lift Force Analysis on Australian Aboriginal Boomerang of Several Design Variations Parameters
The objective of this research is to analyze lift force of Australian Aboriginal boomerang and few other designs based on several design parameters which are variation of area and angle between blades
3D Crane Control
The objective of this project is to design controller for the 3D crane Model that helps to overcome the swinging of the load during the movement of the crane. This model is a mini model of the real life autonomous gantry crane that being used in the industries. The swing motion of the load happens because the behavior of the crane is similar to pendulum by the movement and friction on the load
Methods of improving C02 Sequestration in Saline Aquifer by surface treatment of injected C02
Sequestration of C02 in geologic formations will be part of substantive
campaign to mitigate greenhouse gas (C02) emissions. The risk of leakage from the
target formation due to natural and artificial pathways such as fractures, and fault are
important challenges in geological storage of C02• The leakage arises mainly from the
buoyancy of free-phase mobile C02 (gas or supercritical fluid). The best way for C02 to
be sequestered permanently is by mineralization of C02 and solubility trapping of COz
naturally in the aquifer. Those two processes take a long period of time estimated to
start in 10+ years of time. Alternatives of dissolution of COz prior to injection have
been come up to mitigate risk of leakage during period of the C02 to permanently
naturally sequester.
In this paper, the author investigates a conceptual process in which C02 is
dissolved with chemical prior to injection into the saline formations. As the C02-laden
chemical is denser than native brine containing no C02, it will eliminate the risk of
buoyancy-driven leakage. Several chemicals have been chosen namely Amine solution
(Monoethanolamine and Diethanolamine), Potassium Carbonate and Propylene
Carbonate. Using Aspen Hysys, products from the mixture of COz and chemicals are
evaluated for their properties. The author then investigates and compared the different
product properties. Main properties for evaluation of the products are the density. By
contrasting the injection strategy, the author chose the best injection strategy. In theory,
the injected C02 will mineralize with native rocks and sequestered permanently. Native
saline density of l.lg/cm3 is use for comparing the treated chemical.
Although this alternative may result in higher costs compared to standard
injection strategy, surface dissolution of C02 with chemical may be attractive where the
costs of monitoring or insuring against buoyancy-driven C02 leakage may exceed the
additional cost incurred. The benefit would be to decrease the risk of C02 leakage and
potential harm of environment and people
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