DNA variation in the gene ELTD1 is associated with tick burden in cattle

Ticks and tick‐born diseases are major constraints on cattle production in tropical and subtropical regions in the world. Previously, we identified single nucleotide polymorphisms (SNPs) associated with tick resistance on bovine chromosome 3 at approximately 70 Mb. In this study, we genotyped a dairy (n = 1133) and a beef (n = 774) sample to confirm the association of the intronic SNP rs29019303 and its gene (ELTD1) with tick burden. We genotyped 18 additional SNPs in a region of 181 kb and found that rs29019303 was significantly (P < 0.05) associated with tick burden in both samples with the same favourable allele. A second SNP in this same genomic region was also significantly associated with tick burden in each sample. The associations using haplotypes were stronger than for single markers, including a haplotype of nine tag SNPs that was highly significantly (P = 0.0008) associated with tick counts in the dairy animals. This haplotype and two others were significant after Bonferroni correction for multiple testing. The estimated size of the effects was close to 0.9% of the residual variance in both samples tested.     

Deracemization of aryl ethanols and reduction of acetophenones by whole fungal cells of Aspergillus terreus CCT 4083, A. terreus CCT 3320 and Rhizopus oryzae CCT 4964

The enantioselective deracemization of a number of p-substituted aryl ethanols and the reduction of p-substituted acetophenones were carried out with whole fungal cells of Aspergillus terreus CCT 4083, A. terreus CCT 3320 and Rhizopus oryzae CCT 4964 giving the corresponding alcohols in enantiomeric excesses up to >99%.     

Biochemical characterization and kinetic/thermodynamic study of Aspergillus tamarii URM4634 β-fructofuranosidase with transfructosylating activity

This study reports on the biochemical characterization as well as the kinetic and thermodynamic study of Aspergillus tamarii URM4634 β-fructofuranosidase (FFase) with transfructosylating activity. Conditions for FFase activity were optimized by means of a central composite rotational design using pH and temperature as the independent variables, while residual activity tests carried out in the temperature range of 45–65°C enabled us to investigate FFase thermostability and estimate the kinetic and thermodynamic parameters of enzyme denaturation. Optimal conditions for sucrose hydrolysis and fructosyl transfer catalyzed by crude FFase were 50°C, and pH 6.0 and 7.4, respectively. The thermodynamic properties of irreversible enzyme inactivation were found to be activation energy of 293.1 kJ mol⁻¹, and activation enthalpy, entropy, and Gibbs free energy in the ranges 290.3–290.4 kJ mol⁻¹, 568.7–571.0 J mol⁻¹ K⁻¹, and 97.9–108.8 kJ mol⁻¹, respectively. The results obtained in this study point out satisfactory enzyme activity and thermostability at temperatures commonly used for industrial fructo-oligosaccharide (FOS) synthesis; therefore, this novel FFase appears to be a promising biocatalyst with great potential for long-term FOS synthesis and invert sugar production. To the best of our knowledge, this is the first report on kinetic and thermodynamic parameters of an A. tamarii FFase.     

The use of babassu oil as substrate to produce bioemulsifiers by Candida lipolytica.

Candida lipolytica IA 1055 produced an extracellular emulsifier when using babassu oil as its sole carbon source during batch and fed batch fermentations at 27 degrees C. Emulsification activity was detected after 60 h of growth in all conditions studied. The bioemulsifier was isolated after 144 h of fermentation from the best condition studied. The biopolymer seems to be a polysaccharide-protein-lipid complex.     

Genomic clues of the evolutionary history of Bos indicus cattle

Together with their sister subspecies Bos taurus, zebu cattle (Bos indicus) have contributed to important socioeconomic changes that have shaped modern civilizations. Zebu cattle were domesticated in the Indus Valley 8000 years before present (YBP). From the domestication site, they expanded to Africa, East Asia, southwestern Asia and Europe between 4000 and 1300 YBP, intercrossing with B. taurus to form clinal variations of zebu ancestry across the landmass of Afro‐Eurasia. In the past 150 years, zebu cattle reached the Americas and Oceania, where they have contributed to the prosperity of emerging economies. The zebu genome is characterized by two mitochondrial haplogroups (I1 and I2), one Y chromosome haplogroup (Y3) and three major autosomal ancestral groups (Indian‐Pakistani, African and Chinese). Phenotypically, zebu animals are recognized by their hump, large ears and excess skin. They are rustic, resilient to parasites and capable of bearing the hot and humid climates of the tropics. Many resources are available to study the zebu genome, including commercial arrays of SNP, reference assemblies and publicly available genotypes and whole‐genome sequences. Nevertheless, many of these resources were initially developed to support research and subsidize industrial applications in B. taurus, and therefore they can produce bias in data analysis. The combination of genomics with precision agriculture holds great promise for the identification of genetic variants affecting economically important traits such as tick resistance and heat tolerance, which were naturally selected for millennia and played a major role in the evolution of B. indicus cattle.     

Some Mechanistic Aspects on Fmoc Solid Phase Peptide Synthesis

Peptides are biomolecules that may have several biological activities which makes them important to the environment in which they operate. Sometimes it is necessary for larger amounts of peptides to carry out some studies, like biological tests, NMR structural research or even interaction studies between peptides with other molecules. Expression can be an alternative for that. However, synthesis is specially useful when unnatural modifications or introduction of site specific tags are required. Synthetic peptides have been used for different studies such as cell signaling, development of epitope-specific antibodies, in cell-biology, biomarkers for diseases etc. Many different methodologies for peptide synthesis can be found in the literature. Solid phase peptide synthesis (SPPS) has been largely used and can be an excellent alternative to achieve larger quantities of these biomolecules. In this mini review, we aim to describe the SPPS and explain some of the mechanistic aspects and reagents involved in all phases of the synthesis: the use of resin, the ninhydrin test, some of the protecting groups, coupling reagents for peptide bond formation and the cleavage process.     

In Situ Zymography and Immunolabeling in Fixed and Decalcified Craniofacial Tissues

In situ zymography is a very important technique that shows the proteolytic activity in sections and allows researchers to observe the specific sites of proteolysis in tissues or cells. It is normally performed in non-fixed frozen sections and is not routinely performed in calcified tissues. In this study, we describe a technique that maintains proteolytic activity in fixed and decalcified sections obtained after routine paraffin sectioning in conventional microtome and cryostat sections. We used adult rat hemimandibles, which presented bone, enamel, and dentine matrices; the substrate used was dye-quenched-gelatin. Gelatinolytic activity was colocalized with MMP-2 using fluorescent antibodies. Specific proteolytic activity was observed in all sections, compatible with metalloproteinase activity, particularly in dentine and bone. Furthermore, matrix metalloproteinase-2 was colocalized to the sites of green fluorescence in dentine. In conclusion, the technique presented here will allow in situ zymography reactions in fixed, decalcified, and paraffin-embedded tissues, and we showed that paraformaldehyde-lysine-periodate–fixed cryostat sections are suitable for colocalization of gelatinolytic activity and protein labeling with antibodies. (J Histochem Cytochem 57:615–622, 2009)     

Biotransformations of ortho-, meta- and para-aromatic nitrocompounds by strains of Aspergillus terreus: Reduction of ketones and deracemization of alcohols

Seven strains of the fungus Aspergillus terreus isolated from several provenances in Brazil, catalyzed biotransformations of ortho-, meta- and para-nitrophenyl compounds at different pH values. ortho-Nitroacetophenone and meta-nitroacetophenone were transformed into (S)-(+)-1-(ortho-nitrophenyl)ethanol and (S)-(−)-1-(meta-nitrophenyl)ethanol with high enantiomeric excess (e.e. ≥98%) and conversion (≥98%) by all the strains used. Deracemization of (RS)-1-(meta-nitrophenyl)ethanol was obtained with high selectivity (e.e. up to ≥98%) and good conversion (c 98%). The biotransformations in acidic medium using these fungus strains were more efficient than under basic or neutral conditions.