Research Articles (Biotechnology)

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Browsing by Subject "Agriculture"

Now showing 1 - 7 of 7
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    Analysis of the differentially expressed proteins and metabolic pathways of honeybush (cyclopia subternata) in response to water deficit stress
    (MDPI, 2023) Mahlare, Mary-Jane S; Husselmann, Lizex; Lewu, Muinat N
    Honeybush (Cyclopia spp.) is a rich source of antioxidant properties and phenolic compounds. Water availability plays a crucial role in plant metabolic processes, and it contributes to overall quality. Thus, this study aimed to investigate changes in molecular functions, cellular components, and biological processes of Cyclopia subternata exposed to different water stress conditions, which include well-watered (as Control, T1), semi-water stressed (T2), and water-deprived (T3) potted plants. Samples were also collected from a well-watered commercial farm first cultivated in 2013 (T13) and then cultivated in 2017 (T17) and 2019 (T19). Differentially expressed proteins extracted from C. subternata leaves were identified using LC-MS/MS spectrometry. A total of 11 differentially expressed proteins (DEPs) were identified using Fisher’s exact test (p < 0.00100). Only α-glucan phosphorylase was found to be statistically common between T17 and T19 (p < 0.00100). Notably, α-glucan phosphorylase was upregulated in the older vegetation (T17) and downregulated in T19 by 1.41-fold. This result suggests that α-glucan phosphorylase was needed in T17 to support the metabolic pathway. In T19, five DEPs were upregulated, while the other six were downregulated.
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    Identification and characterization of a heat-inducible Hsp70 gene from Sorghum bicolor which confers tolerance to thermal stress
    (Springer, 2015) Mulaudzi-Masuku, Takalani; Mutepe, Rendani Daphney; Mukhoro, Ofhani Christopher
    This study describes the first detailed molecular characterization of the heat shock protein 70 (Hsp70) gene from Sorghum bicolor, MN1618 designated as SbHsp70-1. The full-length cDNA of SbHsp70-1 consists of 2524 bp with a 1950 bp open reading frame, which encodes a protein of 649 amino acids. SbHsp70-1 is a cytoplasmic protein with high homology to other plant Hsp70s, especially grain crops. Recombinant SbHsp70-1 was able to bind and hydrolyse ATP in a dose-dependent manner, suggesting that SbHsp70-1 functions as an ATPase.
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    Identification of a novel alkaliphilic esterase active at low temperatures by screening a metagenomic library from Antarctic desert soil
    (American Society for Microbiology, 2009) Heath, Caroline; Hu, Xiao Ping; Cary, Craig
    The cold deserts of the McMurdo Dry Valleys, South Victoria Land, Eastern Antarctica, are widely acknowledged as having the harshest soil environments on Earth (6, 8, 26). Despite the apparent hostility of the environment, we and others have reported both unexpectedly high biomass (9) and phylogenetic diversity (1, 19, 24, 29) in Antarctic soils. The presence of numerous novel taxa suggests that these soils might prove to be valuable sources of genetic material for mining novel industrial enzymes active at low temperatures (9, 23). Esterases (EC 3.1.1.1) and lipases (EC 3.1.1.3) catalyze the hydrolysis and synthesis of ester compounds. Their applications in industry cover a broad spectrum, including as detergent additives, in food processing, in environmental bioremediation, and in biomass and plant waste degradation for the production of useful organocompounds (3, 16).
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    Nodulation, leaf harvesting intensity and interval of the black-eyed bean (BEB) (Vigna unguiculata L. Walpers) cowpea type at the University of Zimbabwe, Harare, Zimbabwe
    (Academic Journals, 2012) Matikiti, A.; Chikwambi, Z.; Nyakanda, C.; Mashingaidze, A.B.
    A glasshouse pot experiment was carried out at the University of Zimbabwe, Crop Science Department in 2006 to 2007 rainy season to determine the effect of leaf harvesting intensity and interval on cowpea biological nitrogen fixation through nodulation. The experiment was designed as a three factor factorial. The first factor was leaf harvesting frequency with two levels: leaves harvested weekly or fortnightly. The second factor was leaf harvesting intensity with three levels: harvesting one leaf, two leaves and three leaves per branch. The third factor was soil with two levels: Mutoko sand and UZ red clay soil. The experiment was arranged in a Randomized Complete Block Design (RCBD) with three replications. There was no significant difference (p>0.05) on the number of nodules formed at different intensities and frequency at 6, 9 and 12 weeks after crop emergence. Significant difference (p<0.05) in nodule weight was observed as it decreased with increase in leaf harvesting intensity. Harvesting weekly produced lower nodule weight (0.31 g) than harvesting fortnightly (1.08 g). Mutoko sand soil produced higher nodule weight (0.69 g) than UZ clay soil (0.43 g). Leaf yield increased with increasing leaf harvest intensity, harvesting weekly produced higher yield (10.43 g) than harvesting fortnightly (3.22 g) and Mutoko soil had lower leaf yield than UZ clay soil. There was a significant (p<0.05) difference in seed yield, highest yield was obtained when no leaves were harvested and lowest yield when three leaves were harvested. Soil type effect also significantly (p<0.05) reduced harvestable seed weight from 1.00 g on sand soil to 4.12 g on clay soil. Similar trends were observed for aboveground and total biomass yield. In this study, leaf harvesting intensity and interval has been observed to affect nodulation, grain and biomass yield of glasshouse grown Black-eyed bean (BEB) cowpea. The extent to which these effects were felt also depends on the characteristics of the soil.
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    Post-translational cleavage of recombinantly expressed nitrilase from Rhodococcus rhodochrous J1 yields a stable, active helical form
    (Wiley, 2007) Thuku, Ndoria R.; Weber, Brandon W.; Varsani, Arvind
    Nitrilases convert nitriles to the corresponding carboxylic acids and ammonia. The nitrilase from Rhodococcus rhodochrous J1 is known to be inactive as a dimer but to become active on oligomerization. The recombinant enzyme undergoes post-translational cleavage at approximately residue 327, resulting in the formation of active, helical homo-oligomers. Determining the 3D structure of these helices using electron microscopy, followed by fitting the stain envelope with a model based on homology with other members of the nitrilase superfamily, enables the interacting surfaces to be identified. This also suggests that the reason for formation of the helices is related to the removal of steric hindrance arising from the 39 C-terminal amino acids from the wild-type protein. The helical form can be generated by expressing only residues 1–327.
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    Proteomic analysis of grape berry cell cultures reveals that developmentally regulated ripening related processes can be studied using cultured cells
    (Public Library of Science, 2011) Sharathchandra, Ramaschandra G.; Stander, Charmaine; Ndimba, Bongani
    This work describes a proteomics profiling method, optimized and applied to berry cell suspensions to evaluate organ-specific cultures as a platform to study grape berry ripening. Variations in berry ripening within a cluster(s) on a vine and in a vineyard are a major impediment towards complete understanding of the functional processes that control ripening, specifically when a characterized and homogenous sample is required. Berry cell suspensions could overcome some of these problems, but their suitability as a model system for berry development and ripening needs to be established first.
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    Sustainable agriculture through the enhancement of microbial biocontrol agents: Current challenges and new perspectives
    (MDPI, 2023) Gokul, Arun; Mabaso, Jabulani; Klein, Ashwil
    The future of pesticide usage in agriculture is uncertain due to its unsustainability, adverse environmental impacts, and its association in enhanced phytopathogen resistance. Hence, this situation urges the development of new sustainable practices in agriculture. A promising approach involves endophytes, which are non-pathogenic microorganisms inhabiting the interior parts of plants. However, due to the vast diversity and complexity of plant microbiomes, a major gap has formed with regards to endophytic research and its application in phytopathogen biocontrol. The gap has mainly been increasing due to the difficulty of isolating underrepresented endophytes and due to limitation of previous genetic tools availability to further research and understand plant-microbe interaction, endophytic biocontrol capabilities and their biocontrol compounds.