Summary Growing industrialization and the desire for a better economy in countries has accelerated the emission of greenhouse gases (GHGs), by more than the buffering capacity of the earth's atmosphere. Among the various GHGs, carbon dioxide occupies the first position in the anthroposphere and has detrimental effects on the ecosystem. For decarbonization, several non‐biological methods of carbon capture, utilization and storage (CCUS) have been in use for the past few decades, but they are suffering from narrow applicability. Recently, CO2 emission and its disposal related problems have encouraged the implementation of bioprocessing to achieve a zero waste economy for a sustainable environment. Microbial carbonic anhydrase (CA) catalyses reversible CO2 hydration and forms metal carbonates that mimic the natural phenomenon of weathering/carbonation and is gaining merit for CCUS. Thus, the diversity and specificity of CAs from different micro‐organisms could be explored for CCUS. In the literature, more than 50 different microbial CAs have been explored for mineral carbonation. Further, microbial CAs can be engineered for the mineral carbonation process to develop new technology. CA driven carbonation is encouraging due to its large storage capacity and favourable chemistry, allowing site‐specific sequestration and reusable product formation for other industries. Moreover, carbonation based CCUS holds five‐fold more sequestration capacity over the next 100 years. Thus, it is an eco‐friendly, feasible, viable option and believed to be the impending technology for CCUS. Here, we attempt to examine the distribution of various types of microbial CAs with their potential applications and future direction for carbon capture. Although there are few key challenges in bio‐based technology, they need to be addressed in order to commercialize the technology.

The development of next-generation sequencing (NGS) platforms spawned an enormous volume of data. This explosion in data has unearthed new scalability challenges for existing bioinformatics tools. The analysis of metagenomic sequences using bioinformatics pipelines is complicated by the substantial complexity of these data. In this article, we review several commonly-used online tools for metagenomics data analysis with respect to their quality and detail of analysis using simulated metagenomics data. There are at least a dozen such software tools presently available in the public domain. Among them, MGRAST, IMG/M, and METAVIR are the most well-known tools according to the number of citations by peer-reviewed scientific media up to mid-2015. Here, we describe 12 online tools with respect to their web link, annotation pipelines, clustering methods, online user support, and availability of data storage. We have also done the rating for each tool to screen more potential and preferential tools and evaluated five best tools using synthetic metagenome. The article comprehensively deals with the contemporary problems and the prospects of metagenomics from a bioinformatics viewpoint.

BackgroundSilver nanoparticles (AgNPs) are believed to be emerging tool against various infectious diseases including multi-drug resistant (MDR) bacteria. In the present study, in vitro synthesis of AgNPs was optimized using 1:50 ratio of macerozyme (25 μg/μl) and 1 mM AgNO3 incubated at 80 °C for 8 h. AgNPs were characterized by UV–Visible spectroscopy, dynamic light scattering (DLS), scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy (TEM) and X-ray diffraction (XRD).ResultsCharacterization studies suggest the synthesis of elliptical, stable and crystalline AgNPs with an average size of 38.26 ± 0.4 nm calculated using TEM. The XRD pattern revealed the face-centered-cubic (fcc) form of metallic silver. Good shape integrity and dispersion of AgNPs after 1 year of incubation confirmed their stability. AgNPs were exibited the antimicrobial property against ten pathogenic bacteria, three molds and one yeast. The AgNPs also revealed remarkable antimicrobial activity against three MDR strains i.e. Extended spectrum beta-lactamase positive Escherichia coli, Staphylococcus aureus (MRSA) and Teicoplanin resistant Streptococcus Pneumoniae. The AgNPs coated surgical threads (suture) were revealed the remarkble antibacterial activity against three MDR strains. This is the first report to synthesize antimicrobial elliptical AgNPs using enzymes.Conclusion The results suggest the possibilities to develop the nanoparticles coated antimicrobial medical fabric to combat against MDR infection.Electronic supplementary materialThe online version of this article (doi:10.1186/s12941-017-0216-y) contains supplementary material, which is available to authorized users.

Background: CO 2 in the environment has been a burning issue and aggravated the threats of global warming. Various strategies are being used to decrease the level of releasing CO 2 . Biosequestration is a one of the available nontoxic, robust and eco-friendly approaches but still less evaluated. This study reports the role of microbial Carbonic Anhydrase (CA) in the formation of calcite by utilizing CO 2 . Methods: The marine Nocardiopsis lucentensis was studied for intracellular microbial CA. Isolate grown optimally at 2.5% CO 2 saturated environment and procedure the calcium carbonate encrust in the presence of CaCl 2 . Results: The enzyme was found to catalyze the reaction in a wide range of pH and temperature with an optimum at 7.0 pH and 25°C. The 50 mM NaCl, KCl and MgCl 2 were found to support the enzyme activity and 50 mM ZnCl 2 increases activity 1.5 fold. CA was able to withstand against sulphanilamide inhibitor and stable over prolonged incubation at 4 and 37°C. Conclusion: Calcite formation was evaluated with and without enzyme using marine water as a source of calcium ions. The result of SEM and EDX indicated the formation of larger flower-shaped particles compare to the small cubic particles formed without enzyme. The results suggest that the robustness of enzyme and suitability in the CO 2 capture reactor.

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