Manndideriksen3050

Psychrobacter cryohalolentis strain K5T is a Gram-negative organism first isolated in 2006. It has a complex O-antigen that contains, in addition to l-rhamnose and d-galactose, two diacetamido- and a triacetamido-sugar. The biochemical pathways for the production of these unusual sugars are presently unknown. Utilizing the published genome sequence of the organism, we hypothesized that the genes 0612, 0638, and 0637 encode for a 4,6-dehydratase, an aminotransferase, and an N-acetyltransferase, respectively, which would be required for the biosynthesis of one of the diacetamido-sugars, 2,4-diacetamido-2,4,6-trideoxy-d-glucose, starting from UDP-N-acetylglucosamine. Here we present functional and structural data on the proteins encoded by the 0638 and 0637 genes. The kinetic properties of these enzymes were investigated by a discontinuous HPLC assay. An X-ray crystallographic structure of 0638, determined in its external aldimine form to 1.3 Å resolution, demonstrated the manner in which the UDP ligand is positioned into the active site. It is strikingly different from that previously observed for PglE from Campylobacter jejuni, which functions on the same substrate. Four X-ray crystallographic structures were also determined for 0637 in various complexed states at resolutions between 1.3 and 1.55 Å. Remarkably, a tetrahedral intermediate mimicking the presumed transition state was trapped in one of the complexes. The data presented herein confirm the hypothesized functions of these enzymes and provide new insight into an unusual sugar biosynthetic pathway in Gram-negative bacteria. We also describe an efficient method for acetyl-CoA synthesis that allowed us to overcome its prohibitive cost for this analysis.The insecticidal proteins of Bacillus thuringiensis are used in formulations of spore-crystal complexes and their genes have been incorporated into several crops, providing a model for genetic engineering in agriculture. Despite the variability of the Cry proteins described so far, it is still necessary to look for toxins with a broad spectrum of action, since a significant number of pests are not controlled with the available Cry proteins. It is also important to provide alternatives to address the problem of insect resistance, which has already appeared with the use of formulations and with transgenic plants that express cry genes that code for insecticidal proteins. The FCC 7 strain was characterized by the ultrastructural parasporal body under optical and electronic microscopy, and for the detection of Cry8-type proteins by genomic and proteomic approaches. The identity of the strain and the presence of putative toxin encoding genes, and virulence factors analyzed by Illumina Miseq 1500 platform genomic sequencing, was confirmed. The identity of the two Cry8 proteins that make up the parasporal body was confirmed by MALDI-TOF/TOF. To expand knowledge about the insecticidal activity of this strain, we conducted preliminary tests against the cotton boll weevil, Anthonomus grandis. Here we report the characterization of a novel B. thuringiensis isolate native to Argentina (FCC 7) toxic against A. grandis. The strain shows a rounded parasporal body harboring mainly a protein of about 140 kDa and two different types of Cry8 proteins. Through whole-genome sequencing, we identified the presence of two cry8-like crystal protein genes, one vpa-like and two vpb-like genes, and multiple virulence factors, deepening the knowledge of a strain that had already been described as toxic against some lepidopterans and coleopterans, including Spodoptera frugiperda, Anticarsia gemmatalis, Tenebrio molitor and Diabrotica speciosa.The fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera Noctuidae) is a destructive crop pest native to North, Central, and South America that recently has spread to Africa and Asia. Isolates of Spodoptera frugiperda multiple nucleopolyhedrovirus (SfMNPV) have the potential to be developed as low-risk biopesticides for management of fall armyworm, and a commercially available formulation has been developed for control of fall armyworm in North and South America. In this study, the virulence (LC50 and LT50) of several SfMNPV isolates towards larvae of both corn-strain and rice-strain fall armyworm was assessed. check details Bioassays with corn-strain larvae revealed that the isolates could be organized into fast-killing (LT50 68 h post-infection) groups. Rice-strain larvae exhibited narrower ranges of susceptibility to baculovirus infection and of survival times in bioassays with different isolates. Two SfMNPV isolates with rapid speeds of kill (SfMNPV-459 from Colombia and SfMNPV-1197 from Georgia, USA) along with an isolate that killed corn-strain at relatively low concentrations (SfMNPV-281 from Georgia) were selected for the complete determination of their genome sequences. The SfMNPV-1197 genome sequence shared high sequence identity with genomes of a Nicaraguan isolate, while SfMNPV-281 formed a separate clade with a USA and a Brazilian isolate in phylogenetic trees. The SfMNPV-459 sequence was more divergent with the lowest genome sequence identities in pairwise alignments with other sequenced SfMNPV genomes, and was not grouped reliably with either the 1197 clade or the 281 clade. SfMNPV-459 contained homologs of two ORFs that were unique to another Colombian isolate, but these isolates were not placed in the same clade in phylogenetic trees. This study identifies isolates with superior properties for control of fall armyworm and adds to our knowledge of the genetics of SfMNPV.The perpetual lack of advanced strategies to prevent aggressive breast cancer with multiple categories represents challenging scientific society problems. Reduced graphene oxide- can treat disease, which was recently investigated due to its ability to induce apoptosis-based death. This research tested the chemotherapeutics in vitro efficacy of reduced graphene oxide embedded with gold and silver nanoparticles toward drug-sensitive breast cancer cells (MCF-7) and their cytotoxicity. Synthesis of the Au-Ag/rGO-5FU nanocomposites has been conducted using a wet chemical approach with chitosan aid as a pore directing and capping agent. The particle structure and morphology well characterized using different systems. HR-TEM shows a narrow-sized distribution of less than 100 nm, which is proper for cell membranes and medical use. The physical combination of the nanocomposite and 5-FU drug has been conducted mechanically using wet chemistry. The Au/Ag/rGO-5FU material's high activity enables it to produce reactive oxygen radicals, which display a potential against MCF-7 cell lines.