Microalgae and Cyanobacteria: How Exploiting These Microbial Resources Can Address the Underlying Challenges Related to Food Sources and Sustainable Agriculture: A Review

For thousands of years, crop production has almost entirely depended on conventional agriculture. However, the reality is changing. The ever-growing population, global climate change, soil degradation and biotic/abiotic stresses are a growing threat to food production and security. Thus, sustainable alternatives to increase crop production for a population projected to reach 9.8 billion by 2050 are a major priority. In addition to vertical and soilless farming, innovative products based on bioresources, including plant growth stimulants, have been a target for sustainable food production. Such solutions have led to the exploitation of microorganisms, including microalgae and cyanobacteria as potential bioresources for food and plant biostimulant products. Microalgae (eukaryotic) and cyanobacteria (prokaryotic) are photosynthetic microorganisms with the capacity to synthesize a vast array of bioactive metabolites from atmospheric CO₂ and inorganic nutrients. The present review outlines the nutritional value of microalgae and cyanobacteria as alternative food resources. The potential aspects of microalgae and cyanobacteria as stabilizers of the net change in soil organic carbon (C) levels for reduced farmland degradation are also highlighted. The applications of microalgae and cyanobacteria as remedies for improved soil structure and fertility, and as enhancers of crop productivity and abiotic stress tolerance in agricultural settings are outlined. This review also discusses the co-cultivation of crops with microalgae or cyanobacteria in hydroponic systems to favor optimum root CO₂/O₂ levels for optimized crop production.

     

Purified vesicular stomatitis virus contains an enzyme activity that synthesizes cytidylyl (5'-3') guanosine 5'-triphosphate in vitro

An enzyme activity that synthesizes cytidylyl (5'-3') guanosine 5'-triphosphate (pppGpC) in vitro has been identified in purified vesicular stomatitis virus. The activity is discernible after a lag period which is reduced in length with increasing virus concentration. The lag is eliminated by addition of pppGpC or ppGpC which are effective primers and stimulate dinucleotide synthesis linearly. The requirements of the reaction with respect to MgCl2, NaCl, and temperature are similar to those for viral mRNA synthesis in vitro. The activity, together with the viral L and NS proteins, is removed from virions by treatment with 0.8 M NaCl. The particulate fraction from infected cells that contains the transcribing subviral ribonucleoprotein particles also contains the enzyme activity. The corresponding fraction from uninfected cells does not, indicating that the activity is mediated by virus-specific proteins. Possible functions of the dinucleotide in the life cycle of the virus are discussed.     

Cloning, sequence analysis, and expression of alteration of the mRNA stability gene (ams+) of Escherichia coli.

The ams+ gene, which influences the stability of mRNA in Escherichia coli was cloned in pBR322. The product of the gene, which is a 17,000-dalton protein, was expressed in expression vector pRC23, a derivative of pBR322. The molecular weight is consistent with sequencing analysis which shows that the gene contains 595 nucleotides and has an open reading frame of 149 amino acids. We discussed the possible role(s) of the ams+ gene product in affecting mRNA stability.     

Systematic revision and sexual dimorphism in Choffatia (Ammonoidea: Perisphinctoidea) from the Callovian of Kutch,India

The genus Choffatia (Siemiradzki) is an important Callovian ammonite in Kutch biostratigraphy. Several species of the genus were described by the early workers who did not recognize intraspecific variability and sexual dimorphism in terms of the modern concepts. We have described here three dimorphic species based on material reposited in the Geological Survey of India, Kolkata as well as systematically collected additional specimens with precise stratigraphic information. These species are: Choffatia recuperoi (Gemmellaro, 1873), Choffatia cobra (Waagen, 1875), and Choffatia perdagata (Waagen, 1875). The microconchs of the three species, described here for the first time, are lappeted whereas the macroconchs have a simple aperture. However, these species have similar shell morphologies and they intergrade in shell shape and sculpture; thus it is difficult to distinguish them qualitatively. Statistical analyses (both bivariate and multivariate) support that they are distinct species and there is a good correlation among the degree of involution, the degree of inflation, and the strength of ornamentation. C. cobra is the most evolute, depressed, and strongly ribbed whereas C. perdagata is the most involute, compressed, and weakly ribbed. C. recuperoi occupies the intermediate position. This interspecific diversity of Choffatia thus supports Buckman's Law of Covariation.     

Molecular Basis for the Selective Inhibition of Respiratory Syncytial Virus RNA Polymerase by 2'-Fluoro-4'-Chloromethyl-Cytidine Triphosphate

Respiratory syncytial virus (RSV) causes severe lower respiratory tract infections, yet no vaccines or effective therapeutics are available. ALS-8176 is a first-in-class nucleoside analog prodrug effective in RSV-infected adult volunteers, and currently under evaluation in hospitalized infants. Here, we report the mechanism of inhibition and selectivity of ALS-8176 and its parent ALS-8112. ALS-8176 inhibited RSV replication in non-human primates, while ALS-8112 inhibited all strains of RSV in vitro and was specific for paramyxoviruses and rhabdoviruses. The antiviral effect of ALS-8112 was mediated by the intracellular formation of its 5''-triphosphate metabolite (ALS-8112-TP) inhibiting the viral RNA polymerase. ALS-8112 selected for resistance-associated mutations within the region of the L gene of RSV encoding the RNA polymerase. In biochemical assays, ALS-8112-TP was efficiently recognized by the recombinant RSV polymerase complex, causing chain termination of RNA synthesis. ALS-8112-TP did not inhibit polymerases from host or viruses unrelated to RSV such as hepatitis C virus (HCV), whereas structurally related molecules displayed dual RSV/HCV inhibition. The combination of molecular modeling and enzymatic analysis showed that both the 2''F and the 4''ClCH₂ groups contributed to the selectivity of ALS-8112-TP. The lack of antiviral effect of ALS-8112-TP against HCV polymerase was caused by Asn291 that is well-conserved within positive-strand RNA viruses. This represents the first comparative study employing recombinant RSV and HCV polymerases to define the selectivity of clinically relevant nucleotide analogs. Understanding nucleotide selectivity towards distant viral RNA polymerases could not only be used to repurpose existing drugs against new viral infections, but also to design novel molecules.     

Lidocaine patch (5%) is no more potent than placebo in treating chronic back pain when tested in a randomised double blind placebo controlled brain imaging study

ABSTRACT: The 5% Lidocaine patch is used for treating chronic neuropathic pain conditions such as chronic back pain (CBP), diabetic neuropathy and complex regional pain syndrome, but is effective in a variable proportion of patients. Our lab has reported that this treatment reduces CBP intensity and associated brain activations when tested in an open labelled preliminary study. Notably, effectiveness of the 5% Lidocaine patch has not been tested against placebo for treating CBP. In this study, effectiveness of the 5% Lidocaine patch was compared with placebo in 30 CBP patients in a randomised double-blind study where 15 patients received 5% Lidocaine patches and the remaining patients received placebo patches. Functional MRI was used to identify brain activity for fluctuations of spontaneous pain, at baseline and at two time points after start of treatment (6 hours and 2 weeks). There was no significant difference between the treatment groups in either pain intensity, sensory and affective qualities of pain or in pain related brain activation at any time point. However, 50% patients in both the Lidocaine and placebo arms reported a greater than 50% decrease in pain suggesting a marked placebo effect. When tested against an untreated CBP group at similar time points, the patch treated subjects showed significantly greater decrease in pain compared to the untreated group (n=15). These findings suggest that although the 5% Lidocaine is not better than placebo in its effectiveness for treating pain, the patch itself induces a potent placebo effect in a significant proportion of CBP patients.