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Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus responsible for coronavirus disease of 2019 (COVID-19), has caused havoc around the world. While several COVID-19 vaccines and drugs have been authorized for use, these antiviral drugs remain beyond the reach of most low- and middle-income countries. Rapid viral evolution is reducing the efficacy of vaccines and monoclonal antibodies and contributing to the deaths of some fully vaccinated persons. Others with normal immunity may have chosen not to be vaccinated and remain at risk if they contract the infection. Vaccines may not protect some immunodeficient patients from SARS-CoV-2, who are also at increased risk of chronic COVID-19 infection, a dangerous stalemate between the virus and a suboptimal immune response. Intra-host viral evolution could rapidly lead to the selection and dominance of vaccine and monoclonal antibody-resistant clades of SARS-CoV-2. There is thus an urgent need to develop new treatments for COVID-19. The NZACE2-Pātari project, comprising modified soluble angiotensin-converting enzyme 2 (ACE2) molecules, seeks to intercept and block SARS-CoV-2 infection of the respiratory mucosa. In vitro data presented here show that soluble wild-type ACE2 molecules retain the ability to effectively block the Spike (S) glycoprotein of SARS-CoV-2 variants including the ancestral Wuhan, delta (B.1.617.2) and omicron (B.1.1.529) strains. This therapeutic strategy may prove effective if implemented early during the nasal phase of the infection and may act synergistically with other antiviral drugs such as Paxlovid to further mitigate disease severity., (© The Author(s) 2023. Published by Oxford University Press on behalf of the British Society for Immunology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Aims: This study assessed, at the physiological and molecular levels, the effect of biogas on indole-3-acetic acid (IAA) biosynthesis by Azospirillum brasilense as well as the impact of this bacterium during CO 2 fixation from biogas by Chlorella vulgaris and Scenedesmus obliquus., Methods and Results: IpdC gene expression, IAA production and the growth of A. brasilense cultured under air (control) and biogas (treatment) were evaluated. The results demonstrated that A. brasilense had a better growth capacity and IAA production (105.7 ± 10.3 μg ml -1 ) when cultured under biogas composed of 25% CO 2  + 75% methane (CH 4 ) with respect to the control (72.4 ± 7.9 μg ml -1 ), although the ipdC gene expression level was low under the stressful condition generated by biogas. Moreover, this bacterium was able to induce a higher cell density and CO 2 fixation rate from biogas by C. vulgaris (0.27 ± 0.08 g l -1 d -1 ) and S. obliquus (0.22 ± 0.08 g l -1 d -1 )., Conclusions: This study demonstrated that A. brasilense has the capacity to grow and actively maintain its main microalgal growth-promoting mechanism when cultured under biogas and positively influence CO 2 fixation from the biogas of C. vulgaris and S. obliquus., Significance and Impact of the Study: These findings broaden research in the field of Azospirillum-microalga interactions and the prevalence of Azospirillum in environmental and ecological topics in addition to supporting the uses of plant growth-promoting bacteria to enhance biotechnological strategies for biogas upgrading., (© 2022 The Society for Applied Microbiology.)

Aims: The purpose of this study was to characterize the prokaryotic community and putative microbial interactions between H 2 -producing bacteria (HPB) and non-HPB using two anaerobic sequencing batch biofilm reactors (AnSBBRs) fed with tequila vinasses in co-digestion with acid hydrolysates of Agave tequilana var. azul bagasse (ATAB)., Methods and Results: Two AnSBBRs were operated for H 2 production to correlate changes in physicochemical and biological variables by principal component analysis (PCA). Results indicated that H 2 yield was supported by Ethanoligenens harbinense and Clostridium tyrobutyricum through the PFOR pathway. However, only E. harbinense was able to compete for sugars against non-HPB. Competitive exclusion associated with competition for sugars, depletion of essential trace elements, bacteriocin production and resistance to inhibitory compounds could be carried out by non-HPB, increasing their relative abundances during the dark fermentation (DF) process., Conclusions: The global scenario obtained by PCA correlated the decrease in H 2 production with the lactate:acetate molar ratio in the influent. At the beginning of co-digestion, this ratio had the minimum value considered for a net gain of ATP. This fact could cause the reduction of the relative abundance of C. tyrobutyricum., Significance and Impact of the Study: This is the first study that demonstrated the feasibility of H 2 production by Clostridiales from acid hydrolysates of ATAB in co-digestion with tequila vinasses., (© 2021 The Society for Applied Microbiology.)

Aims: The purpose of this study was to apply cDNA approach for the characterization of active prokaryotic community to understand microbial scenarios and performance of an AnSBR digester fed with acid hydrolysates of Agave tequilana var. azul bagasse (ATAB)., Methods and Results: The digester was implemented for methane production under organic loading rate (OLR) disturbances to correlate physicochemical variables with changes in abundance, diversity and population dynamics of active Bacteria and Archaea by principal components analysis (PCA). Results indicated that methane yield increased as well as active syntrophic relationships for interspecies hydrogen/formate (Anaerolinaceae-Methanobacterium beijingense) and acetate (Anaerolinaceae-Methanosaeta concilii) transfers at 8 g-COD l -1  day -1 . However, methane yield was negatively affected at 16 g-COD l -1  day -1 due to the competition for acetate by active Desulfovibrio marrakechensis and volatile fatty acids inhibition., Conclusions: Microbial scenarios obtained by PCA correlations indicated that methane production from acid hydrolysates of ATAB was feasible at 8 g-COD l -1  day -1 . The digester operation at higher OLR only favoured methanogenesis by the hydrogenotrophic pathway., Significance and Impact of the Study: Only cDNA analysis showed Archaea population dynamics, exhibiting high correlation with physicochemical variables towards the understanding of the methanogenic digester performance during OLR disturbances., (© 2019 The Society for Applied Microbiology.)

Aims: The purpose of this study was to evaluate the effect of warehouse storage conditions on the composition of the fungal community of green coffee beans (GCB) that were stored in jute sacks for 1 year., Methods and Results: Molecular characterization of the fungal community composition and population dynamics obtained by Q-PCR, CE-SSCP (Simpson's diversity index D) and Illumina MiSeq sequencing indicated that Saccharomycetales dominated during the first 6 months of storage period with species as Meyerozyma guilliermondii and Pichia kluyveri. However, after 6 months of storage, the filamentous genus Wallemia became dominant. Principal components analysis correlated this fungal dynamic with storage conditions and other variables as chromaticity (colour), water activity, moisture content, reducing sugars concentration, fungal infection and ochratoxin A production., Conclusions: This study demonstrated that GCB stored in jute sacks after 6 months of storage lead to fungal population dynamics, decreased chromaticity in GCB by bleaching and, then, affected overall quality., Significance and Impact of the Study: Storage plays an important role in the quality evolution during the handling of the GCB. In this context, the composition of the microbial community could be considered a marker to assess the trade value of the coffee beans., (© 2017 The Society for Applied Microbiology.)

The microbial community structure of pig manure slurry (PMS) was determined with comparative analysis of 202 bacterial, 44 archaeal and 33 eukaryotic small subunit (SSU) rDNA partial sequences. Based on a criterion of 97% of sequence similarity, the phylogenetic analyses revealed a total of 108, eight and five phylotypes for the Bacteria, Archaea and Eukarya lineages, respectively. Only 36% of the bacterial phylotypes were closely related (>or=97% similarity) to any previously known sequence in databases. The bacterial groups most often represented in terms of phylotype and clone abundance were the Eubacterium (22% of total sequences), the Clostridium (15% of sequences), the Bacillus-Lactobacillus-Streptococcus subdivision (20% of sequences), theMycoplasma and relatives (10% of sequences) and the Flexibacter-Cytophaga-Bacteroides (20% of sequences). The global microbial community structure and phylotype diversity show a close relationship to the pig gastrointestinal tract ecosystem whereas phylotypes from the Acholeplasma-Anaeroplasma and the Clostridium purinolyticum groups appear to be better represented in manure. Archaeal diversity was dominated by three phylotypes clustering with a group of uncultured microorganisms of unknown activity and only distantly related to the Thermoplasmales and relatives. Other Archaea were methanogenic H2/CO2 utilisers. No known acetoclastic Archaea methanogen was found. Eukaryotic diversity was represented by a pluricellular nematode, two Alveolata, a Blastocystis and an Entamoebidae. Manure slurry physico-chemical characteristics were analysed. Possible inhibitory effects of acetate, sulphide and ammonia concentrations on the microbial anaerobic ecosystem are discussed.

We herein report on our efforts to improve the mapping resolution of a QTL with major effect on milk yield and composition that was previously mapped to bovine chromosome 20. By using a denser chromosome 20 marker map and by exploiting linkage disequilibrium using two distinct approaches, we provide strong evidence that a chromosome segment including the gene coding for the growth hormone receptor accounts for at least part of the chromosome 20 QTL effect. By sequencing individuals with known QTL genotype, we identify an F to Y substitution in the transmembrane domain of the growth hormone receptor gene that is associated with a strong effect on milk yield and composition in the general population.