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Evans AF, O'Brien SR, Ma R, Hager AG, Riggins CW, Lambert KN, Riechers DE. Biochemical characterization of metabolism-based atrazine resistance in Amaranthus tuberculatus and identification of an expressed GST associated with resistance. Plant Biotechnol J 2017; 15:1238-1249. [PMID: 28218978 PMCID: PMC5595711 DOI: 10.1111/pbi.12711] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2016] [Revised: 02/02/2017] [Accepted: 02/08/2017] [Indexed: 05/08/2023]
Abstract
Rapid detoxification of atrazine in naturally tolerant crops such as maize (Zea mays) and grain sorghum (Sorghum bicolor) results from glutathione S-transferase (GST) activity. In previous research, two atrazine-resistant waterhemp (Amaranthus tuberculatus) populations from Illinois, U.S.A. (designated ACR and MCR), displayed rapid formation of atrazine-glutathione (GSH) conjugates, implicating elevated rates of metabolism as the resistance mechanism. Our main objective was to utilize protein purification combined with qualitative proteomics to investigate the hypothesis that enhanced atrazine detoxification, catalysed by distinct GSTs, confers resistance in ACR and MCR. Additionally, candidate AtuGST expression was analysed in an F2 population segregating for atrazine resistance. ACR and MCR showed higher specific activities towards atrazine in partially purified ammonium sulphate and GSH affinity-purified fractions compared to an atrazine-sensitive population (WCS). One-dimensional electrophoresis of these fractions displayed an approximate 26-kDa band, typical of GST subunits. Several phi- and tau-class GSTs were identified by LC-MS/MS from each population, based on peptide similarity with GSTs from Arabidopsis. Elevated constitutive expression of one phi-class GST, named AtuGSTF2, correlated strongly with atrazine resistance in ACR and MCR and segregating F2 population. These results indicate that AtuGSTF2 may be linked to a metabolic mechanism that confers atrazine resistance in ACR and MCR.
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Affiliation(s)
- Anton F. Evans
- Department of Crop SciencesUniversity of Illinois at Urbana‐ChampaignUrbanaILUSA
| | - Sarah R. O'Brien
- Department of Crop SciencesUniversity of Illinois at Urbana‐ChampaignUrbanaILUSA
| | - Rong Ma
- Department of Crop SciencesUniversity of Illinois at Urbana‐ChampaignUrbanaILUSA
| | - Aaron G. Hager
- Department of Crop SciencesUniversity of Illinois at Urbana‐ChampaignUrbanaILUSA
| | - Chance W. Riggins
- Department of Crop SciencesUniversity of Illinois at Urbana‐ChampaignUrbanaILUSA
| | - Kris N. Lambert
- Department of Crop SciencesUniversity of Illinois at Urbana‐ChampaignUrbanaILUSA
| | - Dean E. Riechers
- Department of Crop SciencesUniversity of Illinois at Urbana‐ChampaignUrbanaILUSA
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Devendran S, Abdel-Hamid AM, Evans AF, Iakiviak M, Kwon IH, Mackie RI, Cann I. Multiple cellobiohydrolases and cellobiose phosphorylases cooperate in the ruminal bacterium Ruminococcus albus 8 to degrade cellooligosaccharides. Sci Rep 2016; 6:35342. [PMID: 27748409 PMCID: PMC5066209 DOI: 10.1038/srep35342] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Accepted: 09/28/2016] [Indexed: 12/01/2022] Open
Abstract
Digestion of plant cell wall polysaccharides is important in energy capture in the gastrointestinal tract of many herbivorous and omnivorous mammals, including humans and ruminants. The members of the genus Ruminococcus are found in both the ruminant and human gastrointestinal tract, where they show versatility in degrading both hemicellulose and cellulose. The available genome sequence of Ruminococcus albus 8, a common inhabitant of the cow rumen, alludes to a bacterium well-endowed with genes that target degradation of various plant cell wall components. The mechanisms by which R. albus 8 employs to degrade these recalcitrant materials are, however, not clearly understood. In this report, we demonstrate that R. albus 8 elaborates multiple cellobiohydrolases with multi-modular architectures that overall enhance the catalytic activity and versatility of the enzymes. Furthermore, our analyses show that two cellobiose phosphorylases encoded by R. albus 8 can function synergistically with a cognate cellobiohydrolase and endoglucanase to completely release, from a cellulosic substrate, glucose which can then be fermented by the bacterium for production of energy and cellular building blocks. We further use transcriptomic analysis to confirm the over-expression of the biochemically characterized enzymes during growth of the bacterium on cellulosic substrates compared to cellobiose.
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Affiliation(s)
- Saravanan Devendran
- Energy Biosciences Institute, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.,Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Ahmed M Abdel-Hamid
- Energy Biosciences Institute, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.,Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Anton F Evans
- Energy Biosciences Institute, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.,Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.,School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Michael Iakiviak
- Department of Animal Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - In Hyuk Kwon
- Department of Animal Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Roderick I Mackie
- Energy Biosciences Institute, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.,Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.,Department of Animal Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Isaac Cann
- Energy Biosciences Institute, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.,Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.,School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.,Department of Animal Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.,Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
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Li MJ, Evans AF, Allen DW, Nolan DA. Effects of lateral load and external twist on polarization-mode dispersion of spun and unspun fibers. Opt Lett 1999; 24:1325-1327. [PMID: 18079792 DOI: 10.1364/ol.24.001325] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Using the coupled-mode theory, we have developed a theoretical model to analyze the effects of lateral load and external twist on polarization-mode dispersion (PMD) of spun and unspun fibers. Modeling results show that spun and unspun fibers have very different PMD responses to lateral load and external twist. Experimental results show good agreement with the theory.
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Buckland EL, Boyd RW, Evans AF. Observation of a Raman-induced interpulse phase migration in the propagation of an ultrahigh-bit-rate coherent soliton train. Opt Lett 1997; 22:454-456. [PMID: 18183232 DOI: 10.1364/ol.22.000454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Coherent soliton packets generated in a passively mode-locked fiber laser are transmitted through 23km of dispersion-decreasing fiber. We observe a shift of the phase difference between solitons that is due to intrapulse Raman scattering. We attribute the stability in propagation of these trains to a trade-off between minimizing soliton-soliton interactions by reduction of the pulse width and minimizing this Raman-induced phase migration, which can force the solitons into a deleterious attractive phase relationship. We are thus able to demonstrate the propagation of 177-Gbit/s soliton packets over a distance of 123 soliton periods.
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Williams NE, Hardy PA, Evans AF. Spread of local anaesthetic solutions following sacral extradural (caudal) block: influence of posture. J Spinal Disord 1989; 2:249-53. [PMID: 2535284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Extradural sacral (caudal) block was performed in 17 cases (14 patients) of chronic low back pain. In each case 22 ml of a bupivacaine/methylprednisolone solution incorporating a radioopaque dye was injected over a 2-min period. Patients were randomly assigned to receive the injection in the horizontal position or with 15 degrees head-up or head-down tilt applied to the operating table. Results indicate that analgesia is usually more localised than spread of solution determined by x-ray evidence and that higher levels of analgesia are achieved in patients in the head-up position. Possible causes are the differing distribution characteristics of the constituents of the solution and the gravitational effects of posture on cerebrospinal fluid mechanics. Technical problems associated with obesity, congenital abnormalities, vascular uptake of solution, and delayed spread of the injectant due to adhesions are discussed.
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McConnell CA, Whitehouse GH, Evans AF. Gall-bladder contraction and bile duct opacification in oral cholecystography--a comparison of different methods. Br J Radiol 1983; 56:371-6. [PMID: 6342701 DOI: 10.1259/0007-1285-56-666-371] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
The effect of injection of a cholecystokinetic agent, Ceruletide, was compared with that of the fatty meal following a single dose of Biloptin, and Biloptin with Solubiloptin, in regard to efficiency of gall-bladder contraction, cystic and common bile duct visualisation and side effects. In terms of gall-bladder contraction and ductal delineation no advantage was found from giving Ceruletide or Solubiloptin. Gall-bladder contraction occurred more quickly after Ceruletide than after a fatty meal, with corresponding earlier duct delineation, although the gall bladder was completely emptied of contrast medium in a significant proportion of Ceruletide cases. The incidence of abdominal pain was significantly greater after Ceruletide than after a fatty meal. Because Ceruletide requires an intramuscular injection and has no significant advantage over the fatty meal in regard to gall-bladder contraction and ductal delineation, its use in cholecystography is unjustified. A morning dose of Solubiloptin following Biloptin the previous evening offers no advantage over the Biloptin and fatty meal regimen.
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Abstract
An ICP-monitoring device utilizing an extradural method is described. Clinical and laboratory use has shown it to be easily installed, safe, accurate, and reliable. It can be used with currently available transducers and monitoring equipment. It is hoped that this simple device will encourage the increased use of ICP monitoring.
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Abstract
The study was undertaken to assess the effects of glucagon on biliary tract opacification during intravenous cholangiography. Two series of infusion cholangiograms were obtained at two investigating centres designated A and B. In series A, 41 patients had ioglycamide infusions at a rate of 0.2833 g min-1 over 1 h. In series B, 31 patients had ioglycamide infusions at a rate of 0.3886 g min-1 over 30 min. Radiographs were taken in both series, immediately at the end of the infusion, 10 min later and 30 min after the infusion. Two mg of intravenous glucagon was injected into alternate cases in both series A and B immediately after the first radiograph was taken at the completion of the ioglycamide infusion. Two observers in each series than assessed the radiographic opacification of the biliary system without prior knowledge of which patients had received the glucagon. Delineation of the biliary system was considered better in both series in those patients who received glucagon when compared with the controls. Gallbladder opacification was definitely increased in series A in those receiving glucagon, and a similar tendency was shown in series B. The amount of contrast in the upper intestine was increased in series A in the glucagon group, but not in series B. It is concluded that glucagon improves visualisation of the biliary tract, especially the gallbladder at infusion cholangiography.
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Abstract
A simple technique of venous aortography is described. Eleven patients were examined, 10 with suspected aortic aneurysms. The diagnosis was confirmed in six cases and the relationship of the aneurysm to the renal arteries shown in five of them. Three patients were shown to have a normal aorta. One patient with a suspected saddle embolus was shown to have a normal aorta and iliac arteries. There was one failure but there were no serious complications. The technique is a reliable and simple method of visualising arotic aneurysms, especially if subtraction prints are made.
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Whitehouse GH, Scarrow GD, Evans AF. Initial experiences with a formalised teaching programme in diagnostic radiology during the clinical undergraduate course. Clin Radiol 1979; 30:233-7. [PMID: 436375 DOI: 10.1016/s0009-9260(79)80171-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The initial experiences of a four-week clinical undergraduate attachment in diagnostic radiology are described. The course is divided into (1) a series of prepared lecture programmes which cover aspects of diagnostic radiology in a systematic manner, (2) experience in hospital X-ray departments, observing special investigations and routine reporting, attending clinicoradiological conferences and receiving informal and formal tuition from radiologists, and (3) visits to specialised radiological and other imaging departments, namely ultrasound, nuclear medicine, neuroradiology and paediatrics. The aims of the courses are: (i) to provide a means of teaching clinical subjects and pathology in a dimension which crosses the tightly compartmentalised undergraduate curriculum; (ii) to instil basic principles of radiological interpretation, (iii) to teach undergraduates how to use the facilities of diagnostic imaging departments effectively and efficiently when they have qualified; (iv) to increase interest in the specialty, and insight into student opinion. There are difficulties involved in this large teaching commitment, for instance, understaffing, and the development of the course has been geared to counteracting these problems.
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Abstract
504 patients who had skull radiographs for head injury are included in this study. Only 9 (1.9%) had demonstrable fractures. 129 (25%) of the patients reviewed were admitted to hospital. 93 of these were admitted for up to 24 hours, and 36 for a longer period, usually for conditions unrelated to the head trauma. All but 1 of the patients with a demonstrable skull fracture were admitted to hospital, and the radiographic findings initiated active medical intervention in 2 of these cases. There was no correlation between radiographic findings and the need for hospital admission, and little correlation between radiographic findings and the presenting signs and symptoms. It is, therefore, suggested that the indications for skull radiography in the management of head injuries require reappraisal.
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