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The ribosome, a ribonucleoprotein complex, performs the function of protein translation. While ribosomal RNA catalyzes polypeptide formation, several proteins assist the ribosome throughout the translation process. Studying the biochemical and kinetic properties of these proteins interacting with the ribosome is vital for elucidating their roles. Various techniques, such as zonal centrifugation, pull-down assays, dynamic light scattering (DLS), fluorescence polarization, and surface plasmon resonance (SPR) are employed for this purpose, each presenting unique advantages and limitations. We add to the repertoire of techniques by using Bio-Layer Interferometry (BLI) to examine interactions between the ribosome and translation factors. Our findings demonstrate that BLI can detect interactions of Escherichia coli ribosomes with two proteins: E. coli initiation factor 2 (IF2) and P. falciparum translation enhancing factor (PTEF). A protein (Green Fluorescent Protein; GFP) known not to bind to E. coli ribosomes, shows no binding in the BLI assay. We show that BLI could be used to study the ribosome-protein interactions as it has key advantages like label-free procedures, ease of assay performance, and ribosome sample reuse. Our results highlight the comprehensive use of BLI in studying the ribosome-protein interactions, in addition to studying protein-protein and protein-ligand interactions.

The common intestinal pathogen Klebsiella pneumoniae (K. pneumoniae) is one of the leading causes of fatal superbug infections that can resist the effects of commonly prescribed medicines. The uncontrolled use or misuse of antibiotics has increased the prevalence of drug-resistant K. pneumoniae strains in the environment. In the quest to search for alternative therapeutics for treating these drug-resistant infections, bacteriophages (bacterial viruses) emerged as potential candidates for in phage therapy against Klebsiella. The effective formulation of phage therapy against drug-resistant Klebsiella infections demands thorough characterization and screening of many bacteriophages. To contribute effectively to the formulation of successful phage therapy against superbug infections by K. pneumoniae, this study includes the isolation and characterization of a novel lytic bacteriophage MKP-1 to consider its potential to be used as therapeutics in treating drug-resistant Klebsiella infections. Morphologically, having a capsid attached to a long non-contractile tail, it was found to be a siphovirus that belongs to the class Caudoviricetes and showed infectivity against different strains of the target host bacterium. Comparatively, this double-stranded DNA phage has a large burst size and is quite stable in various physiological conditions. More interestingly, it has the potential to degrade the tough biofilms formed by K. pneumoniae (Klebsiella pneumoniae subsp. pneumoniae (Schroeter) Trevisan [ATCC 15380]) significantly. Thus, the following study would contribute effectively to considering phage MKP-1 as a potential candidate for phage therapy against Klebsiella infection.

The common intestinal pathogen Klebsiella pneumoniae (K. pneumoniae) is one of the leading causes of fatal superbug infections that can resist the effects of commonly prescribed medicines. The uncontrolled use or misuse of antibiotics has increased the prevalence of drug-resistant K. pneumoniae strains in the environment. In the quest to search for alternative therapeutics for treating these drug-resistant infections, bacteriophages (bacterial viruses) emerged as potential candidates for in phage therapy against Klebsiella. The effective formulation of phage therapy against drug-resistant Klebsiella infections demands thorough characterization and screening of many bacteriophages. To contribute effectively to the formulation of successful phage therapy against superbug infections by K. pneumoniae, this study includes the isolation and characterization of a novel lytic bacteriophage MKP-1 to consider its potential to be used as therapeutics in treating drug-resistant Klebsiella infections. Morphologically, having a capsid attached to a long non-contractile tail, it was found to be a siphovirus that belongs to the class Caudoviricetes and showed infectivity against different strains of the target host bacterium. Comparatively, this double-stranded DNA phage has a large burst size and is quite stable in various physiological conditions. More interestingly, it has the potential to degrade the tough biofilms formed by K. pneumoniae (Klebsiella pneumoniae subsp. pneumoniae (Schroeter) Trevisan [ATCC 15380]) significantly. Thus, the following study would contribute effectively to considering phage MKP-1 as a potential candidate for phage therapy against Klebsiella infection. [ABSTRACT FROM AUTHOR]

Translation termination is under strong selection pressure for high speed and accuracy. Here the authors provide a 3D view of the dynamics of a translating bacterial ribosome as it recruits a class-1 release factor (RF1 or RF2) upon encountering a stop codon, and propose a structure-based kinetic model for the early steps in bacterial translation termination.

The initiation of bacterial translation involves the tightly regulated joining of the 50S ribosomal subunit to an initiator transfer RNA (fMet-tRNA.sup.fMet)-containing 30S ribosomal initiation complex to form a 70S initiation complex, which subsequently matures into a 70S elongation-competent complex. Rapid and accurate formation of the 70S initiation complex is promoted by initiation factors, which must dissociate from the 30S initiation complex before the resulting 70S elongation-competent complex can begin the elongation of translation.sup.1. Although comparisons of the structures of the 30S.sup.2-5 and 70S.sup.4,6-8 initiation complexes have revealed that the ribosome, initiation factors and fMet-tRNA.sup.fMet can acquire different conformations in these complexes, the timing of conformational changes during formation of the 70S initiation complex, the structures of any intermediates formed during these rearrangements, and the contributions that these dynamics might make to the mechanism and regulation of initiation remain unknown. Moreover, the absence of a structure of the 70S elongation-competent complex formed via an initiation-factor-catalysed reaction has precluded an understanding of the rearrangements to the ribosome, initiation factors and fMet-tRNA.sup.fMet that occur during maturation of a 70S initiation complex into a 70S elongation-competent complex. Here, using time-resolved cryogenic electron microscopy.sup.9, we report the near-atomic-resolution view of how a time-ordered series of conformational changes drive and regulate subunit joining, initiation factor dissociation and fMet-tRNA.sup.fMet positioning during formation of the 70S elongation-competent complex. Our results demonstrate the power of time-resolved cryogenic electron microscopy to determine how a time-ordered series of conformational changes contribute to the mechanism and regulation of one of the most fundamental processes in biology. A time-resolved cryo-electron microscopy approach is used to visualize, at near-atomic resolution and on a sub-second timescale, short-lived intermediate states of a fundamental biomolecular reaction., Author(s): Sandip Kaledhonkar [sup.1] , Ziao Fu [sup.2] , Kelvin Caban [sup.3] , Wen Li [sup.1] , Bo Chen [sup.1] , Ming Sun [sup.4] , Ruben L. Gonzalez [sup.3] , [...]

Effect of favourable soil and canopy microenvironment, achieved through precision laser land levelling, on rabi sorghum (Maldandi 35-1) productivity was assessed for water deficit regions of Deccan Plateau of India. Laser levelled (0-0.1% grade) and adjoining unlevelled field plots (0.5-2% slope) located at six different experimental sites (silty clay soil) were selected for study. Germination percentage, weed control, temporal soil moisture depletion (SMD), canopy temperature depression (CTD) and water productivity were monitored. SMD ranged 0.46-0.60 for levelled plots indicated no impact of water stress at Panicle emergence stage i.e. 75 day after sowing (DAS). However, grain yield was reduced maximum by 62% when SMD increased from 0.68 to 0.88 for unlevelled plots. Lowering of CTD values by 0.7 to 3.2ºC, in levelled plots indicated the ability of plants to maintain cooler canopy compared to unlevelled plots. Grain yield was reduced by 0.47 t ha-1 with every increase in 0.5% of slope in unlevelled plots, whereas it was negatively correlated with SMD and CTD values in both cases. Laser land levelling showed significant improvement in uniform soil moisture distribution, seed germination, weed control, initial crop establishment and irrigation water productivity. Precision levelling significantly improved soil and canopy microenvironment which favoured to increase the sorghum yield by 27-73% and substantially saved irrigation water (30.9%) compared to unlevelled fields.