Properties and synthesis of the ribulose 1.5 bisphosphate carboxylase large subunit binding protein of Hordeum vulgare

Previous published data have demonstrated that the large subunit of RuBP carboxylase (LSU) synthesised in isolated Pisum sativum (pea) chloroplasts, is associated with a soluble, nuclear-encoded protein. This protein is termed the LSU binding protein (BP) and this observation was confirmed in the present work. The pea BP has previously been shown to consist of two subunits and work presented in this research project has confirmed this observation. Further research on the pea BP revealed that the BP subunits have different isoelectric points, partial proteolytic digestion products and that both subunits are released upon dissociation by ATP and Mg2+ ions. This dissociation is specific to ATP; ADP did not have the same effect. Analysis of soluble Hordeum vulgare (barley) and Triticum aestivum (wheat) chloroplast extracts revealed that proteins with a similar molecular mass to the pea BP cross-reacted immunogenically with antiserum raised against the pea BP. This protein was shown to bind newly- synthesised LSU in isolated barley chloroplasts. Antiserum raised against the barley BP cross-reacted monospecifically with both the barley and pea BP. The barley BP was purified to homogeneity and its physical and chemical characteristics determined. The barley BP was similar to the pea BP in that it consisted of two dissimilar subunits present in equal staining intensities. The barley BP also dissociated to its constituent subunits in the presence of ATP and Mg2+ ions. The physical properties of the barley BP differed in several aspects from those of the pea BP. The native and subunit molecular masses of the barley BP were greater than the pea BP and the isoelectric points and partial proteolytic digestion patterns also differ. The accumulation of the BP during normal leaf development was assayed by rocket immunoelectrophoresis and compared to the accumulation of RuBP carboxylase. Radiolabelling experiments in vivo were also carried out using isolated mesophyll protoplasts and these results suggest that the barley BP subunits (as in pea) are nuclear-encoded. The results presented in this research project are discussed with particular reference to the possible role of the BP in the assembly of RuBP carboxylase

Reclaiming Coal Surface Mines in Central Appalachia: A Case Study of the Benefits and Costs

Regulatory alternatives for the surface mining industry have come under intense public and political scrutiny in recent years. Recent studies have found that the impacts of federal surface mine reclamation regulations\u27 will be noticeable, but perhaps not as substantial as some had expected. Nationwide, coal production from surface mines would be reduced by about five percent, with a similar increase in underground coal production. The federal reclamation legislation, depending on the regulations eventually adopted for its implementation, is unlikely to be a major disruptive influence in the coal industry or a substantial impediment to the long-run national goal of increased utilization of coal. This study has found that the social benefits from surface mine reclamation under existing Kentucky regulations unambiguously exceed the private costs. The incremental benefits of reclamation to satisfy the federal regulations which seem likely to be promulgated are always positive and exceed the incremental private costs under some assumptions, but not under others

742-4 Radial Artery Graft: Angiographic Follow-up

Interest in the use of the radial artery (RA) as a coronary bypass graft has increased. Attention to harvesting and use of perioperative calcium channel inhibitors have ameliorated problems with spasm noted in earlier studies. Since 1993, 72 patients (pts) underwent grafting using a free RA from the non-dominant forearm. Re-angiography was performed in 24 pts to date and is the subject of this study. Pts ranged from 39–79 years (mean 55.5); all had 2 or 3 vessel disease and an average of 3 grafts/pt were constructed (range 2–4). Left internal thoracic artery (L1TA) was used in all cases except 1. The RA was a single graft in 19 including 2 to the LAD system, 12 to the circumflex system and 5 to the RCA. The RA-was sequential in 5 cases. Of the 24 pts catheterized an average of 9 weeks post-op 24/24 RA's were patent: 1 (sequential) RA had a mid-graft stenosis. There was no spasm seen in any RA. RA distal diameters (2.6mm) were well matched to the recipient vessel (RV) (2.2mm). The ratio RV/graft diameter was 0.83 for the radial artery similar to the ratio for the L1TA (0.90).ConclusionThe RA is a viable coronary conduit, easily harvested and has excellent early patency rates

Collaborative Practices and Multidisciplinary Research : The Dialogue Between Entrepreneurship, Management, and Data Science

Author's accepted version (post-print).Available from 06/06/2020.acceptedVersio

"Adulterated" Androstenedione: What FDA's Action against Andro Means for Industry

On March 11, 2004, the Food and Drug Administration (FDA) pronounced that dietary supplement products containing androstenedione were adulterated new dietary ingredients under the Dietary Supplement Health and Education Act of 1994 (DSHEA). The FDA issued a press release, held a news conference, and sent warning letters to 23 companies that had manufactured, marketed or distributed the products containing androstenedione. In its warning letters, FDA threatened possible enforcement actions for noncompliance. The authors have looked at the warning letters, statutes, regulations, and media reports to analyze the legal grounds and standards upon which FDA acted against androstenedione and question the appropriateness of the action taken. They have also looked at the negative impact that FDA's lack of communication and cooperation with Industry is having upon the fitness nutrition industry and the marketing of dietary supplements containing new dietary ingredients. The authors also suggest what might be done to ameliorate this escalating problem including more cooperation between FDA and Industry and more research into the benefits and use of supplement products

Measuring aortic pulse wave velocity using high-field cardiovascular magnetic resonance: comparison of techniques

<p>Abstract</p> <p>Background</p> <p>The assessment of arterial stiffness is increasingly used for evaluating patients with different cardiovascular diseases as the mechanical properties of major arteries are often altered. Aortic stiffness can be noninvasively estimated by measuring pulse wave velocity (PWV). Several methods have been proposed for measuring PWV using velocity-encoded cardiovascular magnetic resonance (CMR), including transit-time (TT), flow-area (QA), and cross-correlation (XC) methods. However, assessment and comparison of these techniques at high field strength has not yet been performed. In this work, the TT, QA, and XC techniques were clinically tested at 3 Tesla and compared to each other.</p> <p>Methods</p> <p>Fifty cardiovascular patients and six volunteers were scanned to acquire the necessary images. The six volunteer scans were performed twice to test inter-scan reproducibility. Patient images were analyzed using the TT, XC, and QA methods to determine PWV. Two observers analyzed the images to determine inter-observer and intra-observer variabilities. The PWV measurements by the three methods were compared to each other to test inter-method variability. To illustrate the importance of PWV using CMR, the degree of aortic stiffness was assessed using PWV and related to LV dysfunction in five patients with diastolic heart failure patients and five matched volunteers.</p> <p>Results</p> <p>The inter-observer and intra-observer variability results showed no bias between the different techniques. The TT and XC results were more reproducible than the QA; the mean (SD) inter-observer/intra-observer PWV differences were -0.12(1.3)/-0.04(0.4) for TT, 0.2(1.3)/0.09(0.9) for XC, and 0.6(1.6)/0.2(1.4) m/s for QA methods, respectively. The correlation coefficients (r) for the inter-observer/intra-observer comparisons were 0.94/0.99, 0.88/0.94, and 0.83/0.92 for the TT, XC, and QA methods, respectively. The inter-scan reproducibility results showed low variability between the repeated scans (mean (SD) PWV difference = -0.02(0.4) m/s and r = 0.96). The inter-method variability results showed strong correlation between the TT and XC measurements, but less correlation with QA: r = 0.95, 0.87, and 0.89, and mean (SD) PWV differences = -0.12(1.0), 0.8(1.7), and 0.65(1.6) m/s for TT-XC, TT-QA, and XC-QA, respectively. Finally, in the group of diastolic heart failure patient, PWV was significantly higher (6.3 ± 1.9 m/s) than in volunteers (3.5 ± 1.4 m/s), and the degree of LV diastolic dysfunction showed good correlation with aortic PWV.</p> <p>Conclusions</p> <p>In conclusion, while each of the studied methods has its own advantages and disadvantages, at high field strength, the TT and XC methods result in closer and more reproducible aortic PWV measurements, and the associated image processing requires less user interaction, than in the QA method. The choice of the analysis technique depends on the vessel segment geometry and available image quality.</p

Comments on "the interpretation of the EPR and Mossbauer spectra of two-iron, one-electron iron-sulfur proteins"

Evidence is presented indicating that the note mentioned in the title is incorrect in two important aspects. 1.) According to our results of ENDOR spectroscopy and computer simulations of Mossbauer spectra, the conclusions drawn are based on an erroneous interpretation of the Mossbauer spectra. 2.) According to quotations from the literature, previous interpretations of experimental data on iron-sulfur proteins are incorrectly represented.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/33508/1/0000005.pd

FAD binding, cobinamide binding and active site communication in the corrin reductase (CobR)

Adenosylcobalamin, the coenzyme form of vitamin B12, is one Nature's most complex coenzyme whose de novo biogenesis proceeds along either an anaerobic or aerobic metabolic pathway. The aerobic synthesis involves reduction of the centrally chelated cobalt metal ion of the corrin ring from Co(II) to Co(I) before adenosylation can take place. A corrin reductase (CobR) enzyme has been identified as the likely agent to catalyse this reduction of the metal ion. Herein, we reveal how Brucella melitensis CobR binds its coenzyme FAD (flavin dinucleotide) and we also show that the enzyme can bind a corrin substrate consistent with its role in reduction of the cobalt of the corrin ring. Stopped-flow kinetics and EPR reveal a mechanistic asymmetry in CobR dimer that provides a potential link between the two electron reduction by NADH to the single electron reduction of Co(II) to Co(I)

The two-iron ferredoxins in spinach, parsley, pig adrenal cortex, Azotobacter vinelandii, and Clostridium pasteurianum: Studies by magnetic field Mossbauer spectroscopy

The two-iron ferredoxins from spinach, parsley, Azotobacter vinelandii, Clostridium pasteurianum and the pig adrenal cortex were investigated by Mossbauer spectroscopy at temperatures from 4 to 256[deg]K and in magnetic fields up to 46 kGauss. Computational programs were devised to allow comparison of the experimental data with computer-simulated spectra in order to facilitate identification of the experimental spectral detail with specific Mossbauer spectroscopic parameters (quadrupole splittings, isomer shifts and nuclear hyperfine and nuclear Zeeman interactions). The results of the analysis permit the following properties of the active center to be established directly as the result of these experiments: 1. 1. In the oxidized forms of the proteins, each iron is in the high spin (S = 5/2) ferric state, spin-coupled to produce a resultant molecular diamagnetism for the protein at temperatures below 100[deg]K.2. 2. In the reduced state of the protein, the active center contains a single ferric site, retaining many properties of the ferric iron in the oxidized protein, but spincoupled to a high spin (S = 2) ferrous site, producing a molecular paramagnetism due to a net electron spin of one half at low temperatures (S = 1/2).3. 3. In spinach and parsley ferredoxins, the ligand symmetry around the ferrous site in the reduced form of the proteins is tetrahedral with measurable axial and rhombic distortions.4. 4. The iron sites in both the oxidized and reduced forms of all the proteins studied are similar, with the possible exception that the ligand symmetry at the ferrous site in the reduced form of the two-iron ferredoxins from C. pasteurianum, A. vinelandii (Azotobacter I and II), and pig adrenal cortex has not been characterized as being square planar or tetrahedral, although octahedral symmetry has been excluded.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/33534/1/0000033.pd