SulTlnlaryTo assess the relationship between melanin production by Cryptococcus neoformans and virulence on a molecular basis, we asked: (a) is CNLAC1, the laccase structural gene of C. neoformans, expressed in vivo?; (b) can mouse virulence be restored to cnlacl (Mel-) mutants by complementation with CNLACI?; and (c) will targeted gene deletion of CNLAC1 decrease virulence for mice? Melanin is produced when cryptococcal laccase catalyzes the oxidation of certain aromatic compounds, including t-dopa, to quinones, which then polymerize to melanin. To assess CNLAC1 transcription, RNA was extracted from C. neoformans in cerebrospinal fluid of infected rabbits. Reverse transcriptase-polymerase chain reaction detected CNLAC1 transcript, indicating that laccase may be produced in the infected host. To assess the effect of CNLAC1 deletion on virulence, a Mel-mutant (10S) was obtained by disruption of the 5' end of the gene. After multiple backcrosses with a parental strain to remove unintended genetic defects introduced by the transformation process, a Mel-progeny was tested and found to be much less virulent for mice than a Mel + progeny. Another Mel-strain (reel2), obtained fromJ.C. Edman (University of California at San Francisco, CA), produced CNLACI transcript but no detectable melanin. Characterization of this mutant revealed a base substitution in CNLA C1 that changed a histidine to tyrosine in a putative copper-binding site. When this base change was introduced into CNLAC1 by site-directed mutagenesis, it no longer transformed mel2 to Mel +, indicating the importance of this histidine in laccase activity. Complementation of a mel2-derived mutant with CNLAC1 restored the Mel + phenotype and increased virulence. These results support the concept that the CNLAC1 gene product has a role in virulence.

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Mango (Mangifera indica) has been recognized as a rich source of bioactive compounds with potential pharmaceutical and nutraceutical applications and has attracted increasing interest from research. Phytochemistry studies have demonstrated that phenolic compounds are one of the most important biologically active components of M. indica extracts. Ultrasound-and microwave-assisted extractions and supercritical fluids have been employed to obtain bioactive molecules, such as phenolic acids, terpenoids, carotenoids, and fatty acids. These phytochemicals exhibit antioxidant, antimicrobial, anti-inflammatory, and anticancer activity, and depending on the source (bark, leaves, seeds, flowers, or peel) and extraction method there will be differences in the structure and bioactivity. This review examines the bioactive compounds, extraction techniques, and biological function of different parts of M. indica of great importance as nutraceuticals and functional compounds with potential application as therapeutic agents and functional foods.

23The aim of this study was to investigate the presence of Escherichia coli carrying mcr-1 gene 24 in domestic animals close to a child who suffered a peritoneal infection by a mcr-1 positive 25 E. coli. Rectal or cloacal swabs and fecal samples from domestic animals were plated on 26 selective media to isolate colistin-resistant E. coli and isolates were submitted to detection of 27 mcr-1 gene, pulsed field gel electrophoresis (PFGE), multi-locus sequence typing (MLST), 28 replicon typing and S1-PFGE. Four mcr-1 positive E. coli isolates (from chicken, turkey and 29 dog) were recovered. No shared PFGE pattern or MLST sequence type were observed among 30 isolates. A 60Kb IncI1 mcr-1-carrying plasmid was detected in all isolates. Our results 31 suggest that mcr-1 gene was horizontally disseminated amongst different lineages of E. coli 32 from domestic animals in the child's household. 33 Importance 34Horizontally transferable colistin resistance (mcr-1 gene) is thought to have originated in 35 domestic animals and transferred to humans through meat and dairy products. In the present 36 report we show evidence that the mcr-1 gene could be transferred to different E. coli strains 37 colonizing different hosts (humans and pets) in the same household. 38 42 different bacterial genera colonizing different animal species (2, 3).43 3The first report of a colistin resistance (CR) gene carried by plasmids (mcr-1) came from China in 44 2015 (4). This gene codes for a phosphoethanolamine transferase (MCR-1), which modifies the 45 lipid A moiety in the outer membrane of Gram negative bacteria and confers resistance to 46 polymyxins (4, 5). Among Enterobacteriacea different mcr gen groups (1-5) could be transferred by 47 PCR was performed to detect mcr gene (4); amplicons were sequence and aligned using mcr-1 130 (NG_055582.1), mcr-2 (NG_051171.1), mcr-3 ( NG_056184.1), mcr-4( MG822665.1), mcr-5 131 (MG384740.1) accession numbers with Geneius software. Pulsed field gel electrophoresis (PFGE) 132 (25) and multilocus sequence typing (MLST) was performed on seven housekeeping genes to 133 define clonal relatedness (26). Replicon typing was performed using a commercial kit (PBRT KIT, 134 DIATHE, Fano, Italy) (20, 27, 28). -lactamase genes (blaCTX-M-1, blaTEM, blaSHV) were detected 135 using primers previously described (29). Briefly, 12,5mL of GoTaq ® Green Master Mix 136 (Promega, Madison, USA) were mixed with 1L of upstream primer, 10M, 1L of downstream 137 primer, 10 L of DNA template and 9,5 L of Nuclease-free water to complete a 25L of 138 reaction volume. The reaction mix were amplified using 2-minute of initial denaturation at 94°C 139 followed by 40 cycles of DNA denaturation at 94°C (40 sec), annealing at 60°C (40sec) and 140 extension at 72°C (1min). The final elongation step at 72°C for 5 min. Amplicons were detected by 141 electrophoresis in a 2% agarose gel. For complete amplification and sequencing of the detected 142resistance genes, primers and conditions previously described were used (30). 143 S1-PFG...

The evaporation rate and corresponding vapor pressure of dicarboxylic acids have been the subject of numerous scientific studies over the years, with reported values spanning several orders of magnitude. Recent work has identified the importance of considering the phase state of the material during evaporation, likely accounting for some of the variability in measured vapor pressures. In the homologous series of dicarboxylic acids, the phase state under dry conditions may be crystalline or amorphous, with particles of odd-carbon-numbered acids exhibiting tendencies to remain amorphous and spherical. Although measurements of vapor pressures for pure components make up most of the available literature data, for many applications, these compounds are not present in isolation. Additionally, many systems containing a semi-volatile material exist in a solid state, especially under dry and low relative humidity conditions. In this work, we explore the evaporation of compounds present in mixed solid-state particles. Specifically, we use single particle levitation coupled with mass spectrometry to measure the evolving composition of solid particles containing mixtures of glutaric acid and succinic acid, glutaric acid and adipic acid, and malonic acid and succinic acid. Under dry conditions, these systems exhibit non-spherical geometries consistent with crystallization of one or both components into an organic crystal. Our measurements allow the evaporation of each component in the mixture to be characterized independently and effective vapor pressures of the pure components to be inferred. The resulting vapor pressures are compared against pure component vapor pressures. We demonstrate that these mixtures exhibit thermodynamic ideality but can be influenced by limited diffusion in the solid phase. These are the first results in the literature that explore the thermodynamic and kinetic factors that control the evaporative evolution of mixed solid-state particles.