Influence of Carbon Source on Cellulase Activity of White-rot and Brown-rot Fungi

Three white-rot fungi, Polyporus versicolor, Ganoderma applanatum, and Peniophora "G," produce an adaptive cellulase complex that can degrade both soluble cellulose (Cx) and microcrystalline cellulose (C1), a highly ordered form of cellulose. Production of Cx and C1 by the white-rot fungi was repressed by simple sugars. Cellulase preparations from three brown-rot fungi, Poria monticola, Lentinus lepideus, and Lenzites trabea, exhibited only Cx activity; microcrystalline cellulose was not significantly degraded. Contrary to the cellulase (Cx) of the white-rot fungi, that of the brown-rot fungi apparently is constitutive, since activity was abundant in cultures with simple sugars or with non-cellulosic polysac-charides as the sole source of carbon. This work disclosed no differences between the cellulase-inducing effects of hardwoods versus those of softwoods that might help explain the preference of white rotters for hardwoods and brown rotters for softwoods

Properties of Cellulases of Two Brown-Rot Fungi and Two White-Rot Fungi

Cellulases from two brown-rot fungi (Cx) and from two white-rot fungi (Cx and C1) were compared. The Cx cellulases of the brown-rot and the white-rot fungi responded differently to pH and temperature effects. Cx activity of the brown-rot fungi was optimum in the low pH region—2 to 3, whereas the activity of the white-rot fungi was considerably lower than optimum. Cx activity of the white-rot fungi was more depressed at low temperatures than was that of the brown-rot fungi. Stability of Cx from the brown-rot fungi was uniform for the range 23 to 60 C, whereas Cx from the white-rot fungi was substantially reduced at temperatures above 50 C. The C1 cellulases produced by only the white-rot fungi were more unstable than those of the Cx to pH and temperature changes. Sulf-hydryl groups apparently are not active sites for any of the cellulases. Degradation of carboxymethylcellulose by Cx was similar for the four fungi and proceeded in a random manner; degradation of microerystalline cellulose by C1 was in an endwise manner, and evidently acts as a β-1-4-glucan cellobiohydrolase. β-glucosidase produced by the four fungi hydrolyzed the cellulase breakdown products to glucose

An Archaeological Survey of a Proposed Dredge Spoil Site in Nueces County, Texas

During December 1983, the Center for Archaeological Research, The University of Texas at San Antonio, conducted an archaeological survey of a proposed dredge spoil site in Nueces County for the Port of Corpus Christi Authority. One site (41 NU 211) was located. Artifacts included one Early Archaic dart point fragment which suggests that 41 NU 211 may date as earl y as 4000 B.C. Limited testing is recommended to evaluate the site unless project plans are altered

A Thermodynamics Based Model for Predicting Piston Engine Performance for Use in Aviation Vehicle Design

Advances in piston engine technology, coupled with high costs of turbine engines have led many general aviation manufacturers to explore the use of piston engines in their smaller vehicles. However, very few engine models are available to analyze piston engine performance. Consequently, designers using vehicle synthesis programs are unable to accurately predict vehicle performance when piston engines are used. This thesis documents the development of a comprehensive, thermodynamics based performance model that meets that need. The first part of this thesis details the basics of piston engine operation, including component geometry and the four stroke engine cycle. Next, the author analyzes the critical components of engine performance, including engine work and power. In developing the engine performance model the Ideal Engine Cycles are discussed. The cold air and fuel-air working fluid models are discussed, along with the types of combustion models, including the Otto Cycle, Diesel Cycle, and the Dual Cycle. Two performance models are generated using the Constant Volume Ideal Engine Cycle: an Ideal Gas Standard Cycle, and a Fuel-Air Cycle. The Ideal Gas Standard Cycle is useful for parametric analysis but lacks the accuracy required for performance calculations. The Fuel-Air Cycle, however, more accurately models the engine cycle and is selected as the basis for the computer program. In developing the computer program the thermodynamic charts used in the Fuel-Air Cycle calculations must be reproduced. To accomplish this, the NASA Chemical Equilibrium Application (CEA) program is integrated into a parent VBA based computer code to provide thermodynamic state point data. Finally, the computer program is correlated to the performance of an existing aviation engine to validate the model.M.S.Committee Chair: Schrage, Daniel; Committee Member: Tai, Jimmy; Committee Member: Waters, Mar

Polysaccharide-Degrading Complex Produced in Wood and in Liquid Media by the Brown-Rot Fungus Poria Placenta

The polysaccharide-degrading enzymes produced by Poria placenta in decayed wood and liquid media were compared qualitatively and quantitatively. A single carbohydrate-degrading complex was isolated and purified from wood and liquid cultures that was active on both polysaccharides and glycosides. Quantitative differences in enzyme activities from decayed wood versus liquid media were observed. However, the purified extracellular carbohydrate-degrading complex isolated from decayed wood and from liquid cultures must be structurally similar because of similar isoelectric points, electrophoretic properties, and molecular sieving properties

Comparison of pectic enzymes in resistant and susceptible mints infected by Verticillium dahliae

Verticillium dahliae Kleb. incites a vascular wilt disease of mints. Susceptible Mentha piperita L. , resistant M. crispa L., and intermediate hybrid 148 were used to study 1) the site of differential resistance and 2) the role of polygalacturonase (PG) in the disease syndrome. Many more V. dahliae propagules were recovered from surface sterilized, finely fragmented, susceptible mint roots than from resistant roots. Therefore, the vascular system of susceptible mint was more extensively invaded than resistant mint. Increase of Verticillium in the stems was dependent on the extent of root invasion; severity of foliar symptoms, in turn, was related to pathogen proliferation in stems. These results indicate that the roots are the first important site of differential resistance. Inoculation through excised shoots showed that mint stems differ in their resistance to Verticillium. Although Verticillium increased similarly in stems of shoot inoculated resistant and susceptible mints, severe symptoms developed only in susceptible M. piperita; resistant M. crispa developed only slight symptoms. PG activity was detected only by the reducing group assay in extracts from diseased mint prepared without a phenolic adsorbent, polyvinylpyrrolidone (PVP). In extracts prepared with PVP, PG was detected by both the viscosity reduction and reducing group assays. Enzyme extracts prepared late in disease when phenol oxidase activity was high showed considerable decrease in viscosity reducing power but not a decrease in reducing groups released from substrate. These results indicate that Verticillium produced an exo -PG in mint that was less affected by phenol oxidation products than the endo -PG. Increase of Verticillium and PG production was similar in shoot inoculated resistant and susceptible mints. Foliar symptoms developed only in susceptible M. piperita and intermediate resistant hybrid 148. No foliar symptoms occurred in resistant M. crispa. Resistance of mint to Verticillium apparently is not due to inactivation of fungal PG. PG production in mints during disease development showed no relationship between symptom severity and PG activity in infected mint stems. A nonpathogen of mint produced PG activity in mint similar to that produced by Verticillium but no wilt symptoms developed. Hypotheses regarding the contribution of PG to wilt symptoms depend on the formation of PGs in diseased plants that hydrolyze pectic substances to large fragments. Enzyme extracts prepared from plants as symptoms increased, liberated a high number of reducing groups from substrate while the viscosity reducing power decreased. This indicated that large pectic fragments are not formed in plants. It was proposed that the role of PG in the Verticillium wilt of mint disease is to provide an additional carbon source for the pathogen

A phase II study of capecitabine and oxalplatin combination chemotherapy in patients with inoperable adenocarcinoma of the gall bladder or biliary tract

Background: Advanced biliary tract carcinomas are associated with a poor prognosis, and palliative chemotherapy has only modest benefit. This multi-centre phase II study was conducted to determine the efficacy of capecitabine in combination with oxaliplatin in patients with inoperable gall bladder or biliary tract cancer. Methods: This was a Phase II, non-randomised, two-stage Simon design, multi-centre study. Ethics approval was sought and obtained by the North West MREC, and then locally by the West Glasgow Hospitals Research Ethics Com mittee. Eligible patients with inoperable locally advanced or metastatic adenocarcinoma of the gall bladder or biliary tract and with adequate performance status, haematologic, renal, and hepatic function were treated with capecit abine (1000 mg/m2 po, twice daily, days 1–14) and oxaliplatin (130 mg/m2 i.v., day 1) every 3 weeks for up to six cycles. The primary objective of the study was to determine the objective tumour response rates (complete and partial). The secondary objectives included assessment of toxicity, progression-free survival, and overall survival. Results: Forty-three patients were recruited between July 2003 and December 2005. The regimen was well tolerated with no grade 3/4 neutropenia or thrombocytopenia. Grade 3/4 sensory neuropathy was observed in six patients. Two-thirds of patients received their chemotherapy without any dose delays. Overall response rate was 23.8 % (95 % CI 12.05–39.5 %). Stable disease was observed in a further 13 patients (31 %) and progressive disease observed in 12 (28.6 %) of patients. The median progression-free survival was 4.6 months (95 % CI 2.8–6.4 months; Fig. 1) and the median overall survival 7.9 months (95 % CI 5.3–10.4 months; Fig. 2). Conclusion: Capecitabine combined with oxaliplatin has a lower disease control and shorter overall survival than the combination of cisplatin with gemcitabine which has subsequently become the standard of care in this disease. How ever, capecitabine in combination with oxaliplatin does have modest activity in this disease, and can be considered as an alternative treatment option for patients in whom cisplatin and/or gemcitabine are contra-indicated

ALS-linked FUS mutations confer loss and gain of function in the nucleus by promoting excessive formation of dysfunctional paraspeckles

Mutations in the FUS gene cause amyotrophic lateral sclerosis (ALS-FUS). Mutant FUS is known to confer cytoplasmic gain of function but its effects in the nucleus are less understood. FUS is an essential component of paraspeckles, subnuclear bodies assembled on a lncRNA NEAT1. Paraspeckles may play a protective role specifically in degenerating spinal motor neurons. However it is still unknown how endogenous levels of mutant FUS would affect NEAT1/paraspeckles. Using novel cell lines with the FUS gene modified by CRISPR/Cas9 and human patient fibroblasts, we found that endogenous levels of mutant FUS cause accumulation of NEAT1 isoforms and paraspeckles. However, despite only mild cytoplasmic mislocalisation of FUS, paraspeckle integrity is compromised in these cells, as confirmed by reduced interaction of mutant FUS with core paraspeckle proteins NONO and SFPQ and increased NEAT1 extractability. This results in NEAT1 localisation outside paraspeckles, especially prominent under conditions of paraspeckle-inducing stress. Consistently, paraspeckle-dependent microRNA production, a readout for functionality of paraspeckles, is impaired in cells expressing mutant FUS. In line with the cellular data, we observed paraspeckle hyper-assembly in spinal neurons of ALS-FUS patients. Therefore, despite largely preserving its nuclear localisation, mutant FUS leads to loss (dysfunctional paraspeckles) and gain (excess of free NEAT1) of function in the nucleus. Perturbed fine structure and functionality of paraspeckles accompanied by accumulation of non-paraspeckle NEAT1 may contribute to the disease severity in ALS-FUS

Broad clinical phenotypes associated with TAR-DNA binding protein (TARDBP) mutations in amyotrophic lateral sclerosis

The finding of TDP-43 as a major component of ubiquitinated protein inclusions in amyotrophic lateral sclerosis (ALS) has led to the identification of 30 mutations in the transactive response-DNA binding protein (TARDBP) gene, encoding TDP-43. All but one are in exon 6, which encodes the glycine-rich domain. The aim of this study was to determine the frequency of TARDBP mutations in a large cohort of motor neurone disease patients from Northern England (42 non-superoxide dismutase 1 (SOD1) familial ALS (FALS), nine ALS-frontotemporal dementia, 474 sporadic ALS (SALS), 45 progressive muscular atrophy cases). We identified four mutations, two of which were novel, in two familial (FALS) and two sporadic (SALS) cases, giving a frequency of TARDBP mutations in non-SOD1 FALS of 5% and SALS of 0.4%. Analysis of clinical data identified that patients had typical ALS, with limb or bulbar onset, and showed considerable variation in age of onset and rapidity of disease course. However, all cases had an absence of clinically overt cognitive dysfunction