1,303 research outputs found
New electrical plethysmograph monitors cardiac output
Four-electrode impedance plethysmograph measures ventricular stroke volume of cardiac output of humans. The instrument is automatic, operates with only one recording channel, and minimizes patient discomfort
Systems biological approaches towards understanding cellulase production by Trichoderma reesei
AbstractRecent progress and improvement in â-omicsâ technologies has made it possible to study the physiology of organisms by integrated and genome-wide approaches. This bears the advantage that the global response, rather than isolated pathways and circuits within an organism, can be investigated (âsystems biologyâ). The sequencing of the genome of Trichoderma reesei (teleomorph Hypocrea jecorina), a fungus that serves as a major producer of biomass-degrading enzymes for the use of renewable lignocellulosic material towards production of biofuels and biorefineries, has offered the possibility to study this organism and its enzyme production on a genome wide scale. In this review, I will highlight the use of genomics, transcriptomics, proteomics and metabolomics towards an improved and novel understanding of the biochemical processes that involve in the massive overproduction of secreted proteins
Identification of potential marker genes for <i>Trichoderma harzianum</i> strains with high antagonistic potential against <i>Rhizoctonia solani</i> by a rapid subtraction hybridization approach
A rapid subtraction hybridization approach was used to isolate genes differentially expressed during mycelial contact between
Trichoderma harzianum (Hypocrea lixii) and Rhizoctonia solani, and could serve as marker genes for selection of superior biocontrol strains. Putatively positive clones were evaluated
by transcription analysis during mycelial contact with R. solani versus growth on glucose, and for their differential transcription between two strains with either strong or poor biocontrol
capability before, at, and after contact with R. solani. Besides four clones, which had similarity to putative but as yet uncharacterized proteins, they comprised ribosomal proteins,
proteins involved in transcriptional switch and regulation, amino acid and energy catabolism, multidrug resistance, and degradation
of proteins and glucans. Transcription of three clones was evaluated in five T. harzianum strains under confrontation conditions with R. solani. Two clones—acetyl-xylane esterase AXE1 and endoglucanase Cel61b—showed significant upregulation during in vivo confrontation
of a T. harzianum strain that successively demonstrated a very high antagonistic capability towards R. solani, while expression was progressively lower in a series of T. harzianum strains with intermediate to poor antagonistic activity. These clones are promising candidates for use as markers in the
screening of improved T. harzianum biocontrol strains
Development and evaluation of an impedance cardiographic system to measure cardiac output and other cardiac parameters Final progress report 1 Jul. 1969 - 31 Dec. 1970
Performance of impedance cardiograph for measuring heart rate and body fluid
Development and Evaluation of an Impedance Cardiographic System to Measure Cardiac Output and Other Cardiac Parameters, 1 July 1968 - 30 June 1969
Impedance cardiographic system to measure cardiac output and cardiovascular function
The phosducin-like protein PhLP1 impacts regulation of glycoside hydrolases and light response in Trichoderma reesei
<p>Abstract</p> <p>Background</p> <p>In the biotechnological workhorse <it>Trichoderma reesei </it>(<it>Hypocrea jecorina</it>) transcription of cellulase genes as well as efficiency of the secreted cellulase mixture are modulated by light. Components of the heterotrimeric G-protein pathway interact with light-dependent signals, rendering this pathway a key regulator of cellulase gene expression.</p> <p>Results</p> <p>As regulators of heterotrimeric G-protein signaling, class I phosducin-like proteins, are assumed to act as co-chaperones for G-protein beta-gamma folding and exert their function in response to light in higher eukaryotes. Our results revealed light responsive transcription of the <it>T. reesei </it>class I phosducin-like protein gene <it>phlp1 </it>and indicate a light dependent function of PhLP1 also in fungi. We showed the functions of PhLP1, GNB1 and GNG1 in the same pathway, with one major output being the regulation of transcription of glycoside hydrolase genes including cellulase genes in <it>T. reesei</it>. We found no direct correlation between the growth rate and global regulation of glycoside hydrolases, which suggests that regulation of growth does not occur only at the level of substrate degradation efficiency.</p> <p>Additionally, PhLP1, GNB1 and GNG1 are all important for proper regulation of light responsiveness during long term exposure. In their absence, the amount of light regulated genes increased from 2.7% in wild type to 14% in Î<it>phlp1</it>. Besides from the regulation of degradative enzymes, PhLP1 was also found to impact on the transcription of genes involved in sexual development, which was in accordance with decreased efficiency of fruiting body formation in Î<it>phlp1</it>. The lack of GNB1 drastically diminished ascospore discharge in <it>T. reesei</it>.</p> <p>Conclusions</p> <p>The heterotrimeric G-protein pathway is crucial for the interconnection of nutrient signaling and light response of <it>T. reesei</it>, with the class I phosducin-like protein PhLP1, GNB1 and GNG1 acting as important nodes, which influence light responsiveness, glycoside hydrolase gene transcription and sexual development.</p
The role of pheromone receptors for communication and mating in Hypocrea jecorina (Trichoderma reesei)
AbstractDiscovery of sexual development in the ascomycete Trichoderma reesei (Hypocrea jecorina) as well as detection of a novel class of peptide pheromone precursors in this fungus indicates promising insights into its physiology and lifestyle. Here we investigated the role of the two pheromone receptors HPR1 and HPR2 in the H. jecorina pheromone-system.We found that these pheromone receptors show an unexpectedly high genetic variability among H. jecorina strains. HPR1 and HPR2 confer female fertility in their cognate mating types (MAT1-1 or MAT1-2, respectively) and mediate induction of fruiting body development. One compatible pheromone precursorâpheromone receptor pair (hpr1âhpp1 or hpr2âppg1) in mating partners was sufficient for sexual development. Additionally, pheromone receptors were essential for ascospore development, hence indicating their involvement in post-fertilisation events.Neither pheromone precursor genes nor pheromone receptor genes of H. jecorina were transcribed in a strictly mating type dependent manner, but showed enhanced expression levels in the cognate mating type. In the presence of a mating partner under conditions favoring sexual development, transcript levels of pheromone precursors were significantly increased, while those of pheromone receptor genes do not show this trend. In the female sterile T. reesei strain QM6a, transcriptional responses of pheromone precursor and pheromone receptor genes to a mating partner were clearly altered compared to the female fertile wild-type strain CBS999.97. Consequently, a delayed and inappropriate response to the mating partner may be one aspect causing female sterility in QM6a
Trichoderma aureoviride: phylogenetic position and characterization
The identity of strains identified as Trichoderma aureoviride/Hypocrea aureoviridis was reconsidered. Trichoderma aureoviride was isolated originally from a specimen identified as H. aureoviridis and thus is H. aureoviridis. The morphological and molecular characters of most strains identified as T. aureoviride differ from those of the ex-type but are more typical of T. harzianum, a member of sect. Pachybasium. Molecular data do not support inclusion of T. aureoviride in sect. Trichoderma, nor was there strong phenotypic similarity between H. aureoviridis and H. rufa. In the ITS phylogeny the T. aureoviride ex-type and other collections of H. aureoviridis form a strongly supported clade that is separate from any other recognized section of Trichoderma. Hypocrea vinosa, which was originally included in the T. aureoviride aggregate species concept, is distinct from T. aureoviride, but closely allied with H. rufa/T. viride. Trichoderma aureoviride/H. aureoviridis is a rare species, restricted to the UK and the Netherlands. We redefine T. aureoviride, limiting it to strains with very slow growth rate, effuse conidiation, and the ITS-1 and 2 sequence type D.Peer Reviewe
Development and evaluation of an impedance cardiographic system to measure cardiac output and other cardiac parameters, July 1, 1967 - June 30, 1968
Impedance cardiograph for monitoring heart functions, and program for computing stroke volume and cardiac output from thoracic impedance changes during cardiac cycl
Identification of potential marker genes for Trichoderma harzianum strains with high antagonistic potential against Rhizoctonia solani by a rapid subtraction hybridization approach.
A rapid subtraction hybridization approach was used to isolate genes differentially expressed during mycelial contact between Trichoderma harzianum (Hypocrea lixii) and Rhizoctonia solani, and could serve as marker genes for selection of superior biocontrol strains. Putatively positive clones were evaluated by transcription analysis during mycelial contact with R. solani versus growth on glucose, and for their differential transcription between two strains with either strong or poor biocontrol capability before, at, and after contact with R. solani. Besides four clones, which had similarity to putative but as yet uncharacterized proteins, they comprised ribosomal proteins, proteins involved in transcriptional switch and regulation, amino acid and energy catabolism, multidrug resistance, and degradation of proteins and glucans. Transcription of three clones was evaluated in five T. harzianum strains under confrontation conditions with R. solani. Two clonesâacetyl-xylane esterase AXE1 and endoglucanase Cel61bâshowed significant upregulation during in vivo confrontation of a T. harzianum strain that successively demonstrated a very high antagonistic capability towards R. solani, while expression was progressively lower in a series of T. harzianum strains with intermediate to poor antagonistic activity. These clones are promising candidates for use as markers in the screening of improved T. harzianum biocontrol strains
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