Edible Mushroom Protein Content and Antioxidant Capacity Increase the Longevity of Anastrepha ludens Fruit Flies.

This study aimed to determine the effect of the protein and antioxidant contents of edible mushrooms on the longevity of the fruit fly (Anastrepha ludens). The contents of protein (Bradford assay), antioxidants (DPPH and ABTS assays), total phenols, and flavonoids in nine strains of different edible mushroom species were determined. Freeze-dried and finely ground complete mushroom fruiting bodies were used to feed the flies, with a concentration of 0.5% in the diet. Male and female fruit flies, both fertile and sterile, were used in this study. Two controls were used: the standard fly diet and a diet supplemented with cinnamon as a food rich in antioxidants. Differences in protein and antioxidant contents were found among the evaluated strains. Differences were also observed in the responses of female and male flies as well as between the responses of fertile and sterile flies. Overall, the sterile flies lived longer. The addition of mushrooms in the diet resulted in greater longevity than in the controls. The use of sterile flies allowed observation of the effect of proteins and antioxidants on reproduction and the subsequent effect of reproduction on longevity.

Biodegradation of recalcitrant compounds and phthalates by culturable bacteria isolated from Liometopum apiculatum microbiota.

Liometopum apiculatum is a species of ants widely distributed in arid and semi-arid ecosystems where there is a relative food shortage compared with tropical ecosystems. L. apiculatum has established an ecological balance involving symbiotic interactions, which have allowed them to survive through mechanisms that are still unknown. Therefore, the aim of this study was to explore the metabolic potential of isolated bacteria from L. apiculatum using enzymatic activity assay and substrate assimilation. Results revealed a complex bacteria consortium belonging to Proteobacteria, Firmicutes, and Actinobacteria phylum. Most of the isolated bacteria showed activities associated with biopolymers degradation, from them Exiguobacterium and B. simplex showed the highest amylolytic activity (27 U/mg protein), while A. johnsonii and B. pumulis showed the highest cellulolytic and xylanolytic activities (1 and 2.9 U/mg protein, respectively). By other hand, some microorganisms such as S. ficaria, E. asburiae, P. agglomerans, A. johnsonii, S. rubidaea, S. marcescens, S. warneri, and M. hydrocarbonoxydans were able to grow up to 1000 mg/L of phthalates esters. These results not only revealed the important contribution of the symbionts in L apiculatum ants feeding habits, but also have shown a promising source of enzymes with potential biotechnological applications such as lignocellulosic biomass hydrolysis and bioremediation processes.

Expression and characterization of a recombinant psychrophilic Cu/Zn superoxide dismutase from Deschampsia antarctica E. Desv. [Poaceae].

We present here the structural modeling and biochemical characterization of a recombinant superoxide dismutase (SOD) from Deschampsia antarctica E. Desv. [Poaceae] produced in Escherichia coli. The recombinant protein was purified by affinity chromatography nickel-nitrilotriacetic acid (Ni-NTA), and its identity was demonstrated by immunoblotting and inhibition by H2O2 and KCN. Inductively coupled plasma optical emission spectroscopy (ICP-OES) analysis confirmed the presence of Cu and Zn. Modeling of the D. antarctica Cu/Zn-SOD (DaSOD) amino acid sequence using the SWISS-MODEL and 2Q2L_B monomer of the psychrophilic Cu/Zu-SOD from Potentilla atrosanguinea (PaSOD) as template produced a structure similar to that of the typical eukaryotic Cu/Zn-SODs. Activity assays using the p-nitro blue tetrazolium chloride (NBT) solution method showed that the purified DaSOD had a specific activity of 5818 U/mg at 25 °C and pH 7.2 and that it was active in a pH interval of 5-8 and a temperature interval of 0-40 °C. Furthermore, DaSOD was still active at -20 °C as observed by a zymogram assay. We found 100 % activity when it was heated at 80 °C for 60 min, indicating a high thermostability. DaSOD properties suggest that this enzyme could be useful for preventing the oxidation of refrigerated or frozen foods, as well as in the preparation of cosmetic and pharmaceutical products.

Analysis of the regulation of the Ustilago maydis proteome by dimorphism, pH or MAPK and GCN5 genes.

Ustilago maydis is a dimorphic corn pathogenic basidiomycota whose haploid cells grow in yeast form at pH7, while at pH3 they grow in the mycelial form. Two-dimensional gel electrophoresis (2-DE) coupled with LC-ESI/MS-MS was used to analyze the differential accumulation of proteins in yeast against mycelial morphologies. 2-DE maps were obtained in the pH range of 5-8 and 404 total protein spots were separated. From these, 43 were differentially accumulated when comparing strains FB2wt, constitutive yeast CL211, and constitutive mycelial GP25 growing at pH7 against pH3. Differentially accumulated proteins in response to pH are related with defense against reactive oxygen species or toxic compounds. Up-accumulation of CipC and down-accumulation of Hmp1 were specifically related with mycelial growth. Changes in proteins that were affected by mutation in the gene encoding the adaptor of a MAPK pathway (CL211 strain) were UM521* and transcription factors Btf3, Sol1 and Sti1. Mutation of GCN5 (GP25 strain) affected the accumulation of Rps19-ribosomal protein, Mge1-heath shock protein, and Lpd1-dihydrolipoamide dehydrogenase. Our results complement the information about the genes and proteins related with the dimorphic transition in U. maydis and changes in proteins affected by mutations in a MAPK pathway and GCN5 gene.

Expansion of human hematopoietic cells from umbilical cord blood using roller bottles in CO2 and CO2-free atmosphere.

In this work, we evaluated the expansion of human hematopoietic stem cells from umbilical cord blood in roller bottles. The Iscove's modified Dulbecco's medium, the Stem Pro 34-SFM medium, and the L-15 Leibovitz's medium for cultures in CO(2)-free atmosphere were assessed. At day 5 of culture, total colony forming unit expansions of 14.44 ± 3.74, 11.20 ± 6.37, and 17.25 ± 3.65-folds were attained, respectively. The expansion reached using L-15 medium in roller bottles was around 10 times higher than that achieved in the static control cultures. To our knowledge, this is the first report of cultures in CO(2)-free atmosphere to expand cord blood human hematopoietic stem cells and it opens a new branch of possibilities for culturing and clinical applications.

Production of penicillin acylase by a recombinant Escherichia coli using cheese whey as substrate and inducer.

Cheese whey (CW) is the major subproduct from cheese manufacturing and it is considered as a waste pollutant since its high content of lactose. In this work a fermentation process for the production of penicillin acylase (PA) by a recombinant Escherichia coli and using CW as unique carbon source and inducer was developed. A design factorial 3(2) was used to evaluate the influence of independent variables (dissolved oxygen and CW concentration) on the ability of E. coli W3110/pPA102 to produce PA. Maximum specific PA activity of 781 U g(-1) was attained at 5 g L(-1) of CW and 3% dissolved oxygen. The results showed that CW can be used successfully as unique carbon source and inducer for the production of recombinant proteins using constructions driven by the lac promoter and this way reducing the discharges of that pollutant to the environment.