Open Access. Powered by Scholars. Published by Universities.®

Biochemistry, Biophysics, and Structural Biology Commons

Open Access. Powered by Scholars. Published by Universities.®

Retrospective Theses and Dissertations

Discipline
Keyword
Publication Year

Articles 1 - 30 of 776

Full-Text Articles in Biochemistry, Biophysics, and Structural Biology

Understanding Protein Motions By Computational Modeling And Statistical Approaches, Lei Yang Jan 2008

Understanding Protein Motions By Computational Modeling And Statistical Approaches, Lei Yang

Retrospective Theses and Dissertations

Because of its appealing simplicity, the elastic network model (ENM) has been widely accepted and applied to study many molecular motion problems, such as the molecular mechanisms of chaperonin GroEL-GroES function, allosteric changes in hemoglobin, ribosome motions, motor-protein motions, and conformational changes in general. In this dissertation, the ENM is employed to study various protein dynamics problems, and its validity is also examined by comparing with experimental data. First, we apply principal component analysis (PCA) to identify the essential protein motions from multiple structures (X-ray, NMR and MD) of the HIV-1 protease. We find significant similarities between the first few ...


Relatedness Of Haemophilus Parasuis Strains And Their Proteins' Possible Roles As Virulence Factors, Emilie Susanna Noel Zehr Jan 2008

Relatedness Of Haemophilus Parasuis Strains And Their Proteins' Possible Roles As Virulence Factors, Emilie Susanna Noel Zehr

Retrospective Theses and Dissertations

Haemophilus parasuis, the causative agent of Glasser's disease, is considered to be a remerging pathogen of swine in high-health status herds. Several molecular typing methods have been suggested as alternatives to serotyping, which failed to identify up to 30% of field isolates. This study compared random amplification of polymorphic DNA (RAPD) profiles and protein profiles of H. parasuis reference strains and field isolates as methods for identifying and grouping virulent and avirulent isolates. DNA and protein profiles of 15 reference strains and 31 field isolates of H. parasuis, analyzed with two computer-based similarity analyses, revealed unique and reproducible DNA ...


Nutritional And Hormonal Modulation Of Diabetes-Perturbed Folate, Homocysteine, And Methyl Group Metabolism, Kristin M. Nieman Jan 2008

Nutritional And Hormonal Modulation Of Diabetes-Perturbed Folate, Homocysteine, And Methyl Group Metabolism, Kristin M. Nieman

Retrospective Theses and Dissertations

Folate, homocysteine, and methyl group metabolism mutually function to provide methyl groups for numerous biosynthetic- and modification-type reactions necessary for optimal health. Methyl groups from these pathways are utilized in the production of important compounds such as nucleic acids, protein, and phospholipids. Thus it is vital to understand the factors that both disrupt and maintain their delicate balance to prevent disease. Disruption of these metabolic pathways is associated with several pathologies including carcinogenesis, birth defects, and vascular disease. Moreover, the disruption of these metabolic pathways may be a link between chronic disease and complications of that disease. Both nutritional and ...


Mechanisms Of Bes1-Regulated Gene Expression Downstream Of Brassinosteroid Signaling In Arabidopsis Thaliana, Xiaofei Yu Jan 2008

Mechanisms Of Bes1-Regulated Gene Expression Downstream Of Brassinosteroid Signaling In Arabidopsis Thaliana, Xiaofei Yu

Retrospective Theses and Dissertations

Brassinosteroids (BRs), the plant steroid hormones, play an important role in mediating plant responses to developmental and environmental cues. BRs signal through a membrane receptor BRI1 and a GSK3 kinase BIN2 to control the activity of BES1/BZR1 family transcription factors. To understand how BES1 regulates gene expression, I looked into both trans-acting protein factors and cis-acting DNA elements that affect BES1 functions, by yeast genetic screen and chromatin immunoprecipitation coupled with DNA microarray (ChIP-chip), respectively. We identified 1609 BES1 direct target genes and discovered conserved DNA motifs in BES1 binding regions. We also showed that BES1 target genes were ...


Molecular Interactions Of The Mammalian Intermediate Filament Protein Synemin With Cytoskeletal Proteins Present In Adhesion Sites, Ning Sun Jan 2008

Molecular Interactions Of The Mammalian Intermediate Filament Protein Synemin With Cytoskeletal Proteins Present In Adhesion Sites, Ning Sun

Retrospective Theses and Dissertations

The type VI intermediate filament (IF) protein synemin is a very large, unique member of the IF protein superfamily. Synemin associates with the major type III IF protein desmin and/or vimentin forming heteropolymeric intermediate filaments (IFs) within mammalian muscle cells. Previous studies in our lab showed that avian synemin interacts with vinculin and alpha-actinin, both of which are cytoskeletal proteins present in adhesion sites such as the focal adhesions within cells. Thus, synemin may link the heteropolymeric IFs to adhesion sites within mammalian muscle cells or within some non-muscle cells that express synemin. At least two isoforms of synemin ...


Studies Of Intermediates And Regulation In Snare-Mediated Membrane Fusion, Xiaobing Lu Jan 2008

Studies Of Intermediates And Regulation In Snare-Mediated Membrane Fusion, Xiaobing Lu

Retrospective Theses and Dissertations

At the synapse, neurotransmitters are released via Ca2+-triggered exocytotic fusion of synaptic vesicles with the presynaptic plasma membrane. The whole process is controlled by various proteins. SNAREs have been recognized as the key components that drive membrane fusion. In addition, many other proteins, such as Munc18/nSec1, Mun13, synaptotagmin, complexin, etc. are characterized to regulate synaptic transmission temporally and spatially.;The in vitro bulk fluorescence assay was applied to examine the kinetics of membrane fusion of liposomes mediated by recombinant neuronal SNAREs and led to the demonstration of hemifusion as an intermediate in the pathway. In order to monitor ...


Characterization Of Barley Yellow Dwarf Virus Subgenomic Rnas, Jacquelyn R. Jackson Jan 2008

Characterization Of Barley Yellow Dwarf Virus Subgenomic Rnas, Jacquelyn R. Jackson

Retrospective Theses and Dissertations

Transcription of subgenomic RNAs (sgRNAs) is a common strategy used by many positive strand RNA viruses of plants and animals to regulate viral gene expression. Barley yellow dwarf virus (BYDV) produces three nested 3'-coterminal subgenomic RNAs in infected cells. SgRNA1 serves as the messenger for the structural and movement proteins. sgRNA2 encodes a small open reading frame (ORF6), that appears not to be translated. The role of sgRNA3 is unknown, as it encodes no ORFs. Neither sgRNA2 nor sgRNA3 is needed for BYDV RNA replication in oat protoplasts. However, sgRNA2 does function as a riboregulator of viral translation in ...


Post-Orbital Color Pattern Variation And The Evolution Of A Radiation Of Turtles (Graptemys), Erin M. Myers Jan 2008

Post-Orbital Color Pattern Variation And The Evolution Of A Radiation Of Turtles (Graptemys), Erin M. Myers

Retrospective Theses and Dissertations

One of the most studied areas in the field of evolutionary biology is the formation and maintenance of new species, as well as variation in the rate and extent to which taxa radiate. A range of evolutionary processes, from ecological adaptation to sexual selection and reinforcement, can lead species formation. However, the generation of new species likely results from several isolating mechanisms acting in concert. The map turtle complex (genus: Graptemys) is an excellent model system for exploring the nature of speciation given its exceptional species richness and morphological diversity, particularly in facial coloration patterns. This research utilizes an integrative ...


Use Of Fourier Transform Infrared (Ftir) Spectroscopy To Determine The Health-Promoting Index (Hpi) Of Cow's Milk, Wendy Leanne Thomas Jan 2008

Use Of Fourier Transform Infrared (Ftir) Spectroscopy To Determine The Health-Promoting Index (Hpi) Of Cow's Milk, Wendy Leanne Thomas

Retrospective Theses and Dissertations

Fourier transform infrared (FTIR) spectroscopy steadily has been gaining popularity for the analysis of milk components including total fat, protein, lactose, and ketones. To date, there have been few descriptions of the use of FTIR spectroscopy for the determination of milk fatty acid composition.;The first objective of this thesis was to develop a method utilizing FTIR spectroscopy for prediction of the health-promoting index (HPI) of milk. The HPI is known to affect the relative softness of butter (Bobe et al., 2003); so, this model could be used to predict which cows' milk could be designated for generation of niche ...


Understanding The Biological Activity Of Hypericum Species Through Metabolomics Studies, Matthew Lee Hillwig Jan 2008

Understanding The Biological Activity Of Hypericum Species Through Metabolomics Studies, Matthew Lee Hillwig

Retrospective Theses and Dissertations

The Hypericum genus contains plants which biosynthesize various polyketides with various known and unknown biological and medicinal activities. However, many Hypericum species have not been chemically or biochemically characterized. These species represent an opportunity for understanding chemical ecology and for new drug discovery research. Acyl-phloroglucinols are of particular interest since they are the most diverse class of specialized metabolites in Hypericum. We used analytical methods such as HPLC, LC-MS and 2-D NMR to screen Hypericum species for metabolite diversity. One species, H. gentianoides, was investigated further based on its historical use by Native Americans and its unique metabolite fingerprint. This ...


The Structure And Mechanism Of Saicar Synthetase, Nathaniel Daum Ginder Jan 2008

The Structure And Mechanism Of Saicar Synthetase, Nathaniel Daum Ginder

Retrospective Theses and Dissertations

SAICAR synthetase catalyzes the eighth step in bacterial de novo purine nucleotide biosynthesis: ATP + L-aspartate + CAIR → ADP + Pi + SAICAR Enzymes involved in nucleotide synthesis are common targets for chemotherapeutic and antimicrobial drugs. They work by reducing the rate of growth of rapidly proliferating cells, thus preventing tumor growth and microbial fecundity. L-Alanosine, an L-aspartate analogue that acts as a substrate for SAICAR synthetase, is a natural product with antiviral and antitumor activities. The product of the reaction is a potent inhibitor of adenylosuccinate synthetase and adenylosuccinate lyase and is responsible for L-alanosine toxicity. L-Alanosine may be effective as a chemotherapeutic ...


Functional Analysis Of The C-Terminal Domain In The Drosophila Jil-1 Histone H3 Kinase, Xiaomin Bao Jan 2008

Functional Analysis Of The C-Terminal Domain In The Drosophila Jil-1 Histone H3 Kinase, Xiaomin Bao

Retrospective Theses and Dissertations

Epigenetic regulation is an important process utilized by biological systems to control gene expression and organize development, with histone modification enzymes among the most important components in this regulatory network. The predominant interphase H3 Serine10 kinase in Drosophila is JIL-1, which plays an important role in regulating chromosome structure and modulating gene expression. The full-length JIL-1 protein is composed of four domains including a N-terminal domain (NTD), two kinase domains (KDI and KDII), and a unique C-terminal domain (CTD). In order to study the biological importance of these individual domains, a domain analysis research approach was taken and different functions ...


A Negative Regulator Of Ribosomal Rna Processing Specifies R-Gene-Independent Cell Death In Barley - Powdery Mildew Interactions, Liu Xi Jan 2008

A Negative Regulator Of Ribosomal Rna Processing Specifies R-Gene-Independent Cell Death In Barley - Powdery Mildew Interactions, Liu Xi

Retrospective Theses and Dissertations

Programmed Cell Death (PCD) plays a pivotal role in plant development and defense. Pathogen dependent cell-death mutants were used to investigate the complex regulatory pathways between PCD and R-gene mediated resistance. Time-course expression profiles of Blumeria graminis f. sp. hordei (Bgh) challenged C.I. 16151 (harboring the Mla6 powdery mildew resistance allele) and its fast-neutron-derived "Bgh-induced tip cell death1" mutant, bcd1, were compared using the 22K Barley1 GeneChip. Contrasts were made to identify genes associated with the cell death phenotype as opposed to R-gene mediated resistance. One hundred eighty-two genes were found in the intersection of these contrasts at a ...


Dissection Of The Mitotic And Nuclear Functions Of Chromator, A Nuclear-Derived Spindle Matrix Component In Drosophila, Yun Ding Jan 2008

Dissection Of The Mitotic And Nuclear Functions Of Chromator, A Nuclear-Derived Spindle Matrix Component In Drosophila, Yun Ding

Retrospective Theses and Dissertations

A spindle matrix has long been proposed to serve as a stationary or elastic molecular matrix substrate for the organization and activities of microtubules and motors, based on the consideration of a mechanical and functional support for the stabilization of microtubule spindle during force generation from mitotic motors. Recently, the identification of four Drosophila proteins, Skeletor, Megator, EAST and Chromator has provided molecular evidence for the existence of this macromolecular matrix structure during mitosis. All of these four proteins have been shown to interact with each other within a protein complex and redistribute from the nucleus at interphase to form ...


Biochemical And Genetic Analyses Of Physical Associations Among Zea Mays Starch Biosynthetic Enzymes, Tracie Ann Hennen-Bierwagen Jan 2008

Biochemical And Genetic Analyses Of Physical Associations Among Zea Mays Starch Biosynthetic Enzymes, Tracie Ann Hennen-Bierwagen

Retrospective Theses and Dissertations

Mutations affecting specific starch biosynthetic enzymes commonly have pleiotropic effects on other enzymes in the same metabolic pathway. Such genetic evidence indicates functional relationships between components of the starch biosynthetic system including starch synthases (SS), starch branching enzymes (BE), and starch debranching enzymes (DBE), however, the molecular explanation for these functional interactions is not known. One possibility is that specific SSs, BEs, and/or DBEs associate physically with each other in multisubunit complexes. To test this hypothesis, this study sought to identify stable associations between SSI, SSIIa, SSIII, SBEI, SBEIIa, and SBEIIb from maize amyloplasts. Three separate detection methods, yeast ...


Phylogenetic Placement And Population Genetic Analysis Of The Endangered Winged Mapleleaf, Quadrula Fragosa, Amanda Heather Hemmingsen Jan 2008

Phylogenetic Placement And Population Genetic Analysis Of The Endangered Winged Mapleleaf, Quadrula Fragosa, Amanda Heather Hemmingsen

Retrospective Theses and Dissertations

The endangered winged mapleleaf, Quadrula fragosa once occurred in the Mississippi, Tennessee, Ohio, and Cumberland River basins in the United States. While the range of this species was thought to have been reduced to a single population in the St. Croix River (Minnesota/Wisconsin), individuals morphologically similar to Q. fragosa were recently recorded in Missouri, Arkansas, and Oklahoma. We employed a phylogenetic analysis of mitochondrial ND1 gene sequences. Our results indicate that Q. fragosa is a separate species and that the southern populations are genetically Q. fragosa. In addition, we developed and utilized 12 microsatellite loci to quantify genetic variation ...


Development Of An Rna Aptamer To Pd173955n Through Selex, Samir Mehanovic Jan 2008

Development Of An Rna Aptamer To Pd173955n Through Selex, Samir Mehanovic

Retrospective Theses and Dissertations

With all the technology available to us, the causes of cancers are still puzzling researchers all over the world. Everyday different approaches are being tested to help cure various cancers. With the development of molecular biology, we are able to understand cancer more at molecular level, which helps us look at different methods to treat cancer patients.;The molecular basis for leukemia cancers are understood to a level where we are able to design treatments that specifically target proteins responsible for the disease. One of those proteins is the Bcr-Abl tyrosine kinase which is mostly responsible for chronic myelogenous leukemia ...


Functional Analysis Of Paralogous Genes In Acetyl Coenzyme A Metabolism, Joel D. Schmidt Jan 2008

Functional Analysis Of Paralogous Genes In Acetyl Coenzyme A Metabolism, Joel D. Schmidt

Retrospective Theses and Dissertations

No abstract provided.


The Locations And Signaling Of H-Ras On Endosomes And Plasma Membrane, Xing Wang Jan 2008

The Locations And Signaling Of H-Ras On Endosomes And Plasma Membrane, Xing Wang

Retrospective Theses and Dissertations

No abstract provided.


Kinetic Studies Of Escherichia Coli And Human Saicar Synthetase, Daniel Joseph Binkowski Jan 2007

Kinetic Studies Of Escherichia Coli And Human Saicar Synthetase, Daniel Joseph Binkowski

Retrospective Theses and Dissertations

Phosphoribosyl-aminoimidazole-succinocarboxamide synthetase (SAICAR synthetase) catalyzes the eighth step of de novo IMP biosynthesis in bacteria, and the seventh step in humans. The SAICAR synthetase reaction is analogous to that of adenylosuccinate synthetase (first committed step of AMP biosynthesis), using ATP to ligate 5-amino-imidazole-4-carboxy ribonucleotide and L-aspartate to produce 5-aminoimidazole-4(N-succinylcarboxamide) ribonucleotide (SAICAR). SAICAR synthetase and other enzymes of purine nucleotide biosynthesis are targets of natural products that impair cell growth. Prior to these studies, the kinetic mechanism of any SAICAR synthetase was unknown. Herein are reported the kinetic mechanisms of bacterial and human SAICAR synthetase activities, the structure of the ...


Taxonomic Review, Phylogeny, And Geographical Population Structure Of The Sawfishes (Chondrichthyes, Pristiformes), Vicente Vieira Faria Jan 2007

Taxonomic Review, Phylogeny, And Geographical Population Structure Of The Sawfishes (Chondrichthyes, Pristiformes), Vicente Vieira Faria

Retrospective Theses and Dissertations

Sawfishes (Pristidae) are considered endangered species worldwide, but their conservation and management have been undermined due to poor understanding of the group's natural taxonomy. The main purpose of this work was to review the taxonomy of sawfishes based on historical taxonomic literature supplemented with empirical observations on morphology, genetics, and geographic distribution. A molecular phylogenetics study based on both mitochondrial and nuclear genes was carried out to estimate the evolutionary interrelationships among the different species of sawfishes. Seven distinct living species are recognized based on external morphology and DNA sequence comparisons. Four are distributed in the Indo-West Pacific, two ...


Structural Study Of Yeast Snare Proteins On Membrane By Epr, Yinghui Zhang Jan 2007

Structural Study Of Yeast Snare Proteins On Membrane By Epr, Yinghui Zhang

Retrospective Theses and Dissertations

Membrane fusion is a basic biophysical process involved in cell's physiological activities. The value of studying the exocytosis of mammalian cells and yeast cells lies in that a highly conserved SNARE (Soluble N-ethylmaleimide-sensitive factor attachment protein receptor) protein super family mediates this process and is proposed to be the core protein machinery for the membrane. The SNARE proteins located on plasma membrane and vesicle membrane are assembled together to form a trans-SNARE bridging two separate membranes and initiating membrane.;My research centers on how SNARE assembly involved in yeast cells' exocytosis promotes membrane fusion between yeast vesicle and plasma ...


Subcellular Location And Function Of A Putative Juvenile Hormone Esterase Binding Protein In Drosophila Melanogaster, Zhiyan Liu Jan 2007

Subcellular Location And Function Of A Putative Juvenile Hormone Esterase Binding Protein In Drosophila Melanogaster, Zhiyan Liu

Retrospective Theses and Dissertations

Insect development, metamorphosis and reproduction are regulated in part by the action of juvenile hormone (JH). The titer of JH is regulated in turn by the action of the enzymes juvenile hormone epoxide hydrolase and juvenile hormone esterase (JHE). Because of the potential for disruption of regulation of insect development through perturbation of the action of JH, the biology of JHE has been well studied. A putative juvenile hormone esterase binding protein, P29 was identified in the tobacco hornworm, Manduca sexta. Following sequencing of the Drosophila melanogaster genome, we identified a homolog of P29 in D. melanogaster, and used this ...


Role Of Leu[Superscript B 10] In Cytoglobin And Comparison Of Direct And Indirect Measurements Of Hexacoordinate Hemoglobin Ligand Affinity, Jordan Richard Witmer Jan 2007

Role Of Leu[Superscript B 10] In Cytoglobin And Comparison Of Direct And Indirect Measurements Of Hexacoordinate Hemoglobin Ligand Affinity, Jordan Richard Witmer

Retrospective Theses and Dissertations

Hexacoordinate hemoglobins (HxHbs) have recently been discovered and have been found in nearly all living organisms. In humans, hxHbs are represented by neuroglobin (Ngb) and cytoglobin (Cgb). While Ngb is principally found in the brain, Cgb is ubiquitously expressed in all tissues. Ligand binding in hexacoordinate hemoglobins is complex due to the reversible coordination of the heme iron by the distal histidine. Hexacoordination regulates ligand binding and is regulated by specific residues in the heme pocket including the B10 position. Therefore, we investigated the influence of LeuB10 on hexacoordination and ligand binding in Cgb. Ligand binding was analyzed for recombinant ...


Biochemical Studies Of Mms6--A Biomineralization Protein, Lijun Wang Jan 2007

Biochemical Studies Of Mms6--A Biomineralization Protein, Lijun Wang

Retrospective Theses and Dissertations

Magnetotactic bacteria are aquatic prokaryotes that can move under the direction of a local geomagnetic field. The magnetosomes found in magnetotactic bacteria are arranged in a single chain or chains, which is the physics basis of magnetotaxis trait. It is believed that with the trait of magnetotaxis, magnetotactic bacteria can simplify their search for the optimal oxygen environments.;Mms6 is a magnetosome membrane-associated protein in Magnetospirillum magneticum strain AMB-1. It has 59 amino acids with a hydrophobic N-terminal and a hydrophilic C-terminal region. Magnetite nanoparticles with similar size and shape to bacterial magnetite can be synthesized in vitro in the ...


Transcriptional Profiling Of Laser-Microdissected Stamen Abscission Zones In Arabidopsis, Suqin Cai Jan 2007

Transcriptional Profiling Of Laser-Microdissected Stamen Abscission Zones In Arabidopsis, Suqin Cai

Retrospective Theses and Dissertations

Organ detachment occurs within cell tiers termed abscission zones (AZs). Characterizations of mutants with aberrant abscission behavior showed abscission to involve multiple signaling pathways. How such pathways are regulated is largely unknown. We examined Arabidopsis abscission zone transcriptome changes associated with floral organ detachment to identify novel shedding regulators. For genomic studies, we used laser capture microdissection (LCM) to dissect AZ cells from surrounding tissues. Because the extremely limited number, small size and close proximity of AZs limited immediate use of LCM, we developed new LCM protocols necessary for genomic studies.;Initial work showed that tape-transfer of paraffin sections to ...


Investigation Of The Peptide-Lipid Interactions Of A Beta-Hairpin Antimicrobial Peptide Using Solid-State Nmr, Rajeswari Mani Jan 2007

Investigation Of The Peptide-Lipid Interactions Of A Beta-Hairpin Antimicrobial Peptide Using Solid-State Nmr, Rajeswari Mani

Retrospective Theses and Dissertations

Solid-state NMR (SSNMR) has gained importance as a versatile tool to elucidate the structure and function of many chemical and biological molecules. In this thesis, we have used SSNMR to study the interactions of an antimicrobial peptide (AMP), Protegrin-1 (PG-1) with membranes of varying lipid composition. Based on our studies we have proposed a model for the mechanism of action of PG-1 with two different lipid membranes. PG-1 is a disulfide-linked beta-sheet peptide with broad-spectrum antimicrobial activities. Similar to many AMPs, it selectively disrupts the anionic membranes of microbial cells but leaves the cholesterol-rich zwitterionic mammalian cell membranes intact.;Studying ...


The Role Of The Integrase C-Terminus In Replication And Targeted Integration Of The Yeast Retrotransposon Ty5, Troy Leon Brady Jan 2007

The Role Of The Integrase C-Terminus In Replication And Targeted Integration Of The Yeast Retrotransposon Ty5, Troy Leon Brady

Retrospective Theses and Dissertations

Mobile genetic elements have the inherent potential to shape the genomes of their hosts. The retroelements, which include the retrotransposons and retroviruses, are a particularly abundant class of mobile elements. The site of retroelement insertion in the host genome is largely determined by the element-encoded protein integrase (IN). Research presented here addresses three aspects of IN from the retrotransposon Ty5: the function of a conserved domain (GKGY) in the IN C-terminus, the role of IN post-translational modification in targeted integration, and the origin of the Ty5 targeting mechanism.;Sequence analysis of a conserved domain (GKGY) found in the C-termini of ...


Characterization Of The Starch Branching Enzymes In Arabidopsis Thaliana, Qinglei Gan Jan 2007

Characterization Of The Starch Branching Enzymes In Arabidopsis Thaliana, Qinglei Gan

Retrospective Theses and Dissertations

The roles of three starch branching enzyme isoforms, BE1, BE2 and BE3, in Arabidopsis leaf starch metabolism were investigated by AtBE mutant analysis. We also determined the expression patterns of BEs in Arabidopsis by GUS staining and microarray experiments. The possible correlation of BE gene expression with other genes in the Arabidopsis genome was analyzed to identify putative genes that are functionally correlated with BEs. Motifs in the promoters of the Arabidopsis BE genes were identified to better understand their expression differences. BE2 and BE3 expression levels during a diurnal cycle were evaluated with isoform specific antibodies. Meantime, the in ...


Crystallographic Analysis Of Parasponia Andersonii Hemoglobin, Andrea Savage Jan 2007

Crystallographic Analysis Of Parasponia Andersonii Hemoglobin, Andrea Savage

Retrospective Theses and Dissertations

The x-ray crystal structure of ferric Parasponia andersonii hemoglobin has been determined to 2.3 A resolution by molecular replacement with Rice hemoglobin 1 (rHb1). By means of absorbance spectroscopy, electrochemistry and x-ray crystallography, it has been revealed that depending on the oxidation state, the heme iron can exsist in either the pentacoordinate or hexacoordinate form. Pentacoordination of the heme iron is found primarily in the deoxy ferrous (2+) form, whereas the ferric (3+) form is exhibited predominantly in bis-histidine coordination. This is unique among known forms of hemoglobins. Furthermore, the crystallographic data has provided evidence which supports previous works ...