Nitrate Reductase Inactivator in a Chlorate Resistant Mutant of the Liverwort, Marchantia paleacea var. diptera

Influx of 13 N"-labelled NO 3 " was studied in roots of intact squash seedlings (Cucurbita max. Duch.) previously grown in nutrient solution without (uninduced) or with NO3" (induced). At the uninduced constitutive level NO 3 " influx was saturable (V max =6.2 μmol (g FW) -1 -h" 1 ; K m =37.0 μM), but it increased again, probably passively, at high external NO 3 " concentrations. Initial NO3" efflux started during induction of the transport system when the influx rate increased and conceivably the NO 3 " concentration in the cytoplasm was raised. Likewise, this tendency was observed after a period of NO 3 " starvation. The kinetic parameters of NO 3 " influx of the substrate-induced high capacity transport system accounted for a V max of 14.0 μmol (gFW) -1 h -1 and a K m of 15 ΜM. Both the uninduced and the induced uptake reacted in a similar pattern to the treatment of inhibitors affecting the protein synthesis (cycloheximide, fluorophenylalanine or puromycin) suggesting a single membrane protein population carrying NO 3 " across the plasmalemma. A rapid onset of a strong inhibition of the NO 3 " influx by the treatment with 1 mM phenyglyoxal was revealed. The influx recovered, but only slowly and was not much enhanced after 5h of recovery at increasing NO 3 " concentrations (100 to 8000 μM) in the ambient solution. 99Copyright© 1992 by Marcel Dekker, Inc.

show abstract

scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.

Contact Info

customersupport@researchsolutions.com

10624 S. Eastern Ave., Ste. A-614

Henderson, NV 89052, USA

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.

Blog Terms and Conditions API Terms Privacy Policy Contact Cookie Preferences Do Not Sell or Share My Personal Information

Made with 💙 for researchers

Part of the Research Solutions Family.

Nitrate Reductase Inactivator in a Chlorate Resistant Mutant of the Liverwort, Marchantia paleacea var. diptera

Cited by 2 publications

References 21 publications

Nitrogen-assimilating enzymes in chlorophyllous cells of the liverwort, Marchantia paleacea var. diptera, grown in the dark

Nitrogen-assimilating enzymes in chlorophyllous cells of the liverwort, Marchantia paleacea var. diptera, grown in the dark

Nitrate fluxes in squash seedlings measured with¹³N

Contact Info

Product

Resources

About

Nitrate Reductase Inactivator in a Chlorate Resistant Mutant of the Liverwort, Marchantia paleacea var. diptera

Cited by 2 publications

References 21 publications

Nitrogen-assimilating enzymes in chlorophyllous cells of the liverwort, Marchantia paleacea var. diptera, grown in the dark

Nitrogen-assimilating enzymes in chlorophyllous cells of the liverwort, Marchantia paleacea var. diptera, grown in the dark

Nitrate fluxes in squash seedlings measured with13N

Contact Info

Product

Resources

About

Nitrate fluxes in squash seedlings measured with¹³N