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Mycobacterium tuberculosis (Mtb) is a slow-growing, intracellular pathogen that exhibits a high GC-rich genome. Several factors, including the GC content of the genome, influence the evolution of specific codon usage biases in genomes. As a result, the Mtb genome exhibits strong biases for amino acid usage and codon usage. Codon usage of mRNAs affects several aspects of translation, including accuracy, efficiency, and protein folding. Here we address the effect of codon usage biases in determining the translation efficiency of mRNAs in Mtb. Unlike most commonly studied organisms, Mtb carries a single copy of each tRNA gene. However, we show that the relative levels of tRNAs in the Mtb tRNA pool vary by an order of magnitude. Our results show that the codons decoded by the abundant tRNAs indeed show higher adaptability. Moreover, there is a general positive correlation between genomic codon usage and the tRNA adaptability of codons (TAc). We further estimated the optimality of the codon and mRNAs by considering both the TAc and the tRNA demand. These measures did not show any correlation with mRNA abundance and translation efficiency. There was no correlation between tRNA adaptability and ribosome pausing as well. Taken together, we conclude that the translation machinery, and the tRNA pool of an organism, co-evolve with the codon usage to optimize the translation efficiency of an organism. Thus the deleterious effect of maladapted codons is not pronounced.

Indian agri-food supply chain (AFSC) is highly unorganized in terms of flow of products, funds, and information, resulting in low profitability of farmers. In this paper, we have identified various internal factors (strengths and weaknesses) and external factors (opportunities and threats) of AFSC to make a strategic viewpoint. Based on the identified factors, questionnaire are prepared and circulated among experts from academics and industries to prioritize the identified factors. Further, analytical hierarchy process (AHP) and Fuzzy-AHP methods are used to rank the identified strengths, weaknesses, opportunities and threats factors followed by comparative analysis. The results reveal that agriculture sectors significant contribute in national growth and it is a highest ranked strength. Small farm holding farmers is a major weakness of Indian agriculture system. These factors need to be addressed in designing of Indian AFSC, which has capability to stimulate the growth of overall agriculture sector as well as the nation.