Many microorganisms are able to use plant-derived aromatic and cyclic compounds like the common plant secondary metabolite quinic acid as carbon and energy sources. In fungi, three enzymatic steps convert quinic acid into the common intermediate protocatechuic acid, which is then further converted into TCA cycle intermediates. The genes encoding these three enzymes are known to be part of a gene cluster in Neurospora crassa along with a permease, a gene of unknown function, and an activator-repressor module controlling expression of the cluster.
View Article and Find Full Text PDFAppl Environ Microbiol
December 2023
Ruminants play a key role in the conversion of cellulolytic plant material into high-quality meat and milk protein for humans. The rumen microbiome is the driver of this conversion, yet there is little information on how gene expression within the microbiome impacts the efficiency of this conversion process. The current study investigates gene expression in the rumen microbiome of beef heifers and bison and how transplantation of ruminal contents from bison to heifers alters gene expression.
View Article and Find Full Text PDFThe feruloyl esterase B gene () is specifically induced by hydroxycinnamic acids (e.g. ferulic acid, caffeic acid and coumaric acid) but the transcriptional regulation network involved in induction and ferulic acid metabolism has only been partially addressed.
View Article and Find Full Text PDFTannic acid, a hydrolysable gallotannin present in plant tissues, consists of a central glucose molecule esterified with gallic acid molecules. Some microorganisms, including several species, can metabolize tannic acid by releasing gallic acid residues from tannic acid by secreting tannic acid specific esterases into the medium. The expression of these so-called tannases is induced by tannic acid or gallic acid.
View Article and Find Full Text PDFis an important filamentous fungus in industrial biotechnology for the production of citric acid and enzymes. In the late 1980s, the N400/NRRL3 strain was selected for both fundamental and applied studies in relation to several processes including gluconic acid and protein production. To facilitate handling of , the N400 wild-type strain was UV mutagenized in two consecutive rounds to generate N401 and N402.
View Article and Find Full Text PDFThe transcription factor GaaR is needed for the expression of genes required for pectin degradation and transport and catabolism of the main degradation product, D-galacturonic acid (GA) in Aspergillus niger. In this study, we used the strong constitutive gpdA promoter of Aspergillus nidulans to overexpress gaaR in A. niger.
View Article and Find Full Text PDFThe expression of genes encoding extracellular polymer-degrading enzymes and the metabolic pathways required for carbon utilization in fungi are tightly controlled. The control is mediated by transcription factors that are activated by the presence of specific inducers, which are often monomers or monomeric derivatives of the polymers. A D-galacturonic acid-specific transcription factor named GaaR was recently identified and shown to be an activator for the expression of genes involved in galacturonic acid utilization in Botrytis cinerea and Aspergillus niger Using a forward genetic screen, we isolated A.
View Article and Find Full Text PDFWe present a novel framework for jointly tracking a camera in 3D and reconstructing the 3D model of an observed object. Due to the region based approach, our formulation can handle untextured objects, partial occlusions, motion blur, dynamic backgrounds and imperfect lighting. Our formulation also allows for a very efficient implementation which achieves real-time performance on a mobile phone, by running the pose estimation and the shape optimisation in parallel.
View Article and Find Full Text PDFThe Ste20/PAK family is involved in many cellular processes, including the regulation of actin-based cytoskeletal dynamics and the activation of MAPK signaling pathways. Despite its numerous roles, few of its substrates have been identified. To better characterize the roles of the yeast Ste20p kinase, we developed an in vitro biochemical genomics screen to identify its substrates.
View Article and Find Full Text PDFWe present a real-time algorithm which can recover the 3D trajectory of a monocular camera, moving rapidly through a previously unknown scene. Our system, which we dub MonoSLAM, is the first successful application of the SLAM methodology from mobile robotics to the "pure vision" domain of a single uncontrolled camera, achieving real time but drift-free performance inaccessible to Structure from Motion approaches. The core of the approach is the online creation of a sparse but persistent map of natural landmarks within a probabilistic framework.
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