Paps Reductase
Paps Reductase - Related Videos
08:45
Isothermal Titration Calorimetry for Measuring Macromolecule-Ligand Affinity
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Cited by 84 •
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A general protocol for the use of isothermal titration calorimetry to monitor the binding thermodynamics for biological systems with moderate binding affinities is presented.
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Pelvic Exam II: Speculum Exam
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Photosystem I
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2019
Although structurally similar to photosystem II (PSII), photosystem I (PSI) is has a different electron supplier and electron acceptor. Both these photosystems work in concert. An excited electron from PSII is relayed to PSI via an electron transport chain in the thylakoid membrane of the chloroplast, which is comprised of the carrier molecule plastoquinone, the dual-protein cytochrome complex, and plastocyanin. As electrons move between PSII and PSI, they lose energy and must be re-energized...
10:31
Multicolor Time-lapse Imaging of Transgenic Zebrafish: Visualizing Retinal Stem Cells Activated by Targeted Neuronal Cell Ablation
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Cited by 41 •
2010
In this video, techniques for multicolor confocal time-lapse imaging and targeted cell ablation are provided. Time-lapse imaging is used to monitor the behavior of multiple cell types of interest in vivo. Targeted cell ablation facilitates the study neural circuit function and cell-specific neuronal regeneration paradigms.
09:39
Technique to Collect Fungiform (Taste) Papillae from Human Tongue
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Cited by 30 •
2010
Knowledge of molecular mechanisms underlying gustatory transduction has recently enjoyed significant advances, largely due to using animal models. However, the wide diversity in taste sensitivity and specificity among mammals warrants studies in human tissue. We describe a biopsy technique to collect living taste cells from the papillae on human tongue.
FAQs
Thioredoxin commonly supplies the reducing equivalents required for PAPS reductase activity. These reducing equivalents enable cleavage of the activated sulfate group in PAPS, allowing sulfite and 3′-phosphoadenosine-5′-phosphate, or PAP, to form. This dependence links the enzyme’s activity to the cell’s reducing environment and helps explain how electron transfer supports sulfur assimilation.
The two products connect the enzyme reaction to different parts of cellular metabolism. Sulfite serves as the sulfur-containing intermediate that can be reduced further to sulfide, whereas PAP is the phosphorylated adenosine product released when the activated sulfate group is cleaved. Tracking both products therefore helps characterize the reaction and its metabolic consequences.
By producing sulfite from activated sulfate, PAPS reductase helps direct sulfur into a form that can enter subsequent assimilation steps. Further reduction to sulfide permits incorporation into cysteine and other sulfur-containing compounds. Through this sequence, the enzyme connects sulfur acquisition with the distribution of sulfur into protein synthesis, cofactor production, and broader cellular metabolism.
Research on PAPS reductase can clarify how organisms obtain and distribute sulfur rather than examining sulfur-containing molecules in isolation. The enzyme provides a focused point for investigating sulfur assimilation, the use of reducing equivalents, and the transition from activated sulfate to sulfite. These questions are relevant to microbial physiology, plant nutrition, enzyme function, and sulfur cycling.
A useful conceptual analysis follows sulfur beyond the enzyme’s immediate product. PAPS reductase generates sulfite, which can then be reduced to sulfide before sulfur is incorporated into cysteine. Examining this sequence helps relate enzyme activity to the formation of a sulfur-containing amino acid and to the supply of sulfur for protein synthesis.
The enzyme is relevant in both areas because sulfur assimilation supports the production of essential sulfur-containing cellular compounds. In microbial physiology, it can help frame how cells manage sulfur acquisition and metabolism. In plant nutrition, it provides context for how sulfur is converted into forms that contribute to cysteine, cofactors, and other metabolic products.