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751.
Bacterial NO reductases (NOR) catalyze the reduction of NO into N2O, either as a step in denitrification or as a detoxification mechanism. cNOR from Paracoccus (P.) denitrificans is expressed from the norCBQDEF operon, but only the NorB and NorC proteins are found in the purified NOR complex.Here, we established a new purification method for the P. denitrificans cNOR via a His-tag using heterologous expression in E. coli. The His-tagged enzyme is both structurally and functionally very similar to non-tagged cNOR. We were also able to express and purify cNOR from the structural genes norCB only, in absence of the accessory genes norQDEF. The produced protein is a stable NorCB complex containing all hemes and it can bind gaseous ligands (CO) to heme b3, but it is catalytically inactive. We show that this deficient cNOR lacks the non-heme iron cofactor FeB. Mutational analysis of the nor gene cluster revealed that it is the norQ and norD genes that are essential to form functional cNOR. NorQ belongs to the family of MoxR P-loop AAA+ ATPases, which are in general considered to facilitate enzyme activation processes often involving metal insertion. Our data indicates that NorQ and NorD work together in order to facilitate non-heme Fe insertion. This is noteworthy since in many cases Fe cofactor binding occurs spontaneously. We further suggest a model for NorQ/D-facilitated metal insertion into cNOR. 相似文献
752.
753.
Flexible Services and Manufacturing Journal - Customers in the manufacturing sector, especially in the automotive industry, have a high demand for individualized products at price levels comparable... 相似文献
754.
Hubbard Tru Cove Michael V. Green Austin M. Iannarilli Fabiola Allen Maximilian L. LaRose Summer H. Nagy Chris Compton Justin A. Lafferty Diana J.R. 《Biodiversity and Conservation》2022,31(11):2607-2624
Biodiversity and Conservation - Mammalian carnivores are elusive and enigmatic species that often play keystone roles in ecosystems through direct and indirect effects. Growing evidence shows that... 相似文献
755.
Debra Van Egeren Javier Escabi Maximilian Nguyen Shichen Liu Christopher R. Reilly Sachin Patel Baransel Kamaz Maria Kalyva Daniel J. DeAngelo Ilene Galinsky Martha Wadleigh Eric S. Winer Marlise R. Luskin Richard M. Stone Jacqueline S. Garcia Gabriela S. Hobbs Fernando D. Camargo Franziska Michor Sahand Hormoz 《Cell Stem Cell》2021,28(3):514-523.e9
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756.
Richard V. Burkhauser John Cawley Maximilian D. Schmeiser 《Economics & Human Biology》2009,7(3):307-318
There are several ways to measure fatness and obesity, each with its own strengths and weaknesses. The primary measure for tracking the prevalence of obesity has historically been body mass index (BMI). This paper compares long-run trends in the prevalence of obesity when obesity is defined using skinfold thickness instead of BMI, using data from the full series of U.S. National Health Examination Surveys. The results indicate that when one uses skinfold thickness rather than BMI to define obesity, the rise in the prevalence of obesity is detectable 10-20 years earlier. This underscores the importance of examining multiple measures of fatness when monitoring or otherwise studying obesity. 相似文献