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The native Eurasian wild boar (Sus scrofa ) is a reservoir of Mycobacterium bovis , the causative agent of animal tuberculosis (TB), a chronic disease in livestock, companion animals and wild mammals. Cases of M. bovis infection in wild boar or feral pig have been reported worldwide, making early detection a priority in the eradication of the disease. Point‐of‐care diagnostic tests, such as low cost lateral flow assays, provide high specificity and sensitivity and can be performed on site , an essential requirement for a rapid screening of wildlife. A lateral flow assay, LFA, (INgezim TB CROM Ab) for the detection of M. bovis ‐specific antibodies in wild boar serum and blood has been developed based on MPB83, one of the major immunogenic antigens of the bacterium. A total of 140 samples of wild boar serum, well‐characterized by Mycobacterium tuberculosis complex culture and TB compatible post‐mortem lesions, have been analysed with LFA, and results were compared with one in‐house and two commercial Enzyme‐linked Immunosorbent Assays (ELISA), INgezim TB Porcine and INgezim Tuberculosis DR. In experimental samples, the achieved values of sensitivity of the different techniques ranged from 84.3% to 92.1% and the specificity was 100% in all of them. In field animals, specificity ranged from 96% to 100%, whereas sensitivity ranged from 48% to 64% in juvenile wild boar, increasing to 93.3%–100% in adult wild boar. In particular, the total sensitivity and specificity values obtained with the new LFA were 83% and 97%, respectively, indicating that INgezim TB CROM Ab could be used as a first approach for the surveillance of TB in wild boar, with a special applicability for animal‐side testing., Part of this research was funded by the EU, Seventh Research Framework Program FP7‐KBBE‐2013‐7 under grant number nº 613799 (WildTBVac). This is a contribution to the WildDriver grant CGL2017‐89866 from MINECO and EU‐FEDER. We are very grateful to Dr. Mercedes Dominguez and her laboratory (Instituto de Salud Carlos III, Unidad de Inmunología Microbiana, Majadahonda, Spain) for their generous supply of P22 protein complex.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has infected more than 8 million people worldwide, becoming a pandemic. Detecting antibodies against SARS-CoV-2 is of utmost importance and a good indicator of exposure and circulation of the virus within the general population. Two serological tools based on a double recognition assay [enzyme-linked immunosorbent assay (DR-ELISA) and lateral flow assay (DR-LFA)] to detect total antibodies to SARS-CoV-2 have been developed based on the recombinant nucleocapsid protein. A total of 1065 serum samples, including positive for COVID-19 and negative samples from healthy donors or infected with other respiratory pathogens, were analyzed. The results showed values of sensitivity between 91.2% and 100%, and specificity of 100% and 98.2% for DR-LFA and DR-ELISA, respectively. No cross-reactivity against seasonal coronavirus (HCoV-NL63, HCoV-229E, HCoV-HKU1, HCoV-OC43) was found. These results demonstrate the importance of serology as a complementary tool to polymerase chain reaction for follow-up of recovered patients and identification of asymptomatic individuals.

13 p.-7 fig.-1 tab., The emergence and spread of antibiotic-resistant bacteria is pushing the need of alternative treatments. In this context, phage therapy is already a reality to successfully fight certain multiresistant bacteria. Among different phage gene products, murein hydrolases responsible of phage progeny liberation (also called lysins or endolysins) are weapons that target specific peptidoglycan bonds, leading to lysis and death of susceptible bacteria when added from the outside. In the pneumococcal system, all but one phage murein hydrolases reported to date share a choline-binding domain that recognizes cell walls containing choline residues in the (lipo)teichoic acids. Some purified pneumococcal or phage murein hydrolases, as well as several chimeric proteins combining natural catalytic and cell wall-binding domains (CBDs) have been used as effective antimicrobials. In this work we have constructed a novel chimeric N-acetylmuramoyl-L-alanine amidase (PL3) by fusing the catalytic domain of the Pal amidase (a phage-coded endolysin) to the CBD of the LytA amidase, the major pneumococcal autolysin. The physicochemical properties of PL3 and the bacteriolytic effect against several pneumococci (including 48 multiresistant representative strain) and related species, like Streptococcus pseudopneumoniae, Streptococcus mitis, and Streptococcus oralis, have been studied. Results have shown that low doses of PL3, in the range of 0.5–5 mg/ml, are enough to practically sterilize all choline-containing strains tested. Moreover, a single 20-mg dose of PL3 fully protected zebrafish embryos from infection by S. pneumoniae D39 strain. Importantly, PL3 keeps 95% enzymatic activity after 4 weeks at 37 C and can be lyophilized without losing activity, demonstrating a remarkable robustness. Such stability, together with a prominent efficacy against a narrow spectrum of human pathogens, confers to PL3 the characteristic to be an effective therapeutic. In addition, our results demonstrate that the structure/functionbased domain shuffling approach is a successful method to construct tailor-made endolysins with higher bactericidal activities than their parental enzymes., Research wasfunded by grants from the Ministerio de Economía y Competitividad (MINECO) to PG (SAF2012-39444- C02-01) and MM (BFU2012-36825 and BFU2015-70052-R), the Consejería de Educación de la Comunidad de Madrid (S2010/BMD/2457) to MM. Additional funding was provided by the CIBER de Enfermedades Respiratorias (CIBERES),an initiative of the Instituto de Salud Carlos III (ISCIII).

In recent years, glycosiltransferases have arisen as standard biocatalysts for the enzymatic synthesis of a wide variety of natural and non-natural nucleosides. Such enzymatic synthesis of nucleoside analogs catalyzed by nucleoside phosphorylases and 2'-deoxyribosyltransferases (NDTs) has demonstrated to be an efficient alternative to the traditional multistep chemical methods, since chemical glycosylation reactions include several protection-deprotection steps. This minireview exhaustively covers literature reports on this topic with the final aim of presenting NDTs as an efficient option to nucleoside phosphorylases for the synthesis of natural and non-natural nucleosides. Detailed comments about structure and catalytic mechanism of described NDTs, as well as their possible biological role, substrate specificity, and advances in detection of new enzyme specificities towards different non-natural nucleoside synthesis are included. In addition, optimization of enzymatic transglycosylation reactions and their application in the synthesis of natural and non-natural nucleosides have been described. Finally, immobilization of NDTs is shown as a practical procedure which leads to the preparation of very interesting biocatalysts applicable to industrial nucleoside synthesis. 3.811 JCR (2013) Q1, 32/165 Biotechnology & applied microbiology