Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • 1975-1979  (2)
  • 1915-1919
  • Nitrate reductase  (2)
Material
Years
  • 1975-1979  (2)
  • 1915-1919
Year
  • 1
    ISSN: 1432-2048
    Keywords: Antimetabolites ; Cell culture ; Enzyme induction ; Molybdenum ; Nitrate reductase ; Rosa, Paul's Scarlet
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Induction of nitrate reductase (EC 1.6.6.1) activity was measured in Paul's Scarlet rose cell suspensions cultured in media containing nitrate (NO 3 - ) or urea (U) as nitrogen source, and with (+Mo) or without molybdenum (-Mo). There was a lag of 30 min during induction by NO 3 - in +Mo cultures but no lag occurred during induction after adding Mo to NO 3 - -Mo or to U-Mo cultures preincubated with NO 3 - . Actinomycin D, cycloheximide, and puromycin completely blocked induction by NO 3 - , but had no effect on the initial rate of induction by Mo. Cycloheximide and puromycin blocked induction by NO 3 - more quickly than actinomycin D. Induction by NO 3 - appeared to involve mRNA-dependent synthesis of apoprotein followed by rapid activation with molybdenum in intact cells independently of protein synthesis. Nitrate-induced apoprotein appeared less stable than the holoenzyme. When induced by NO 3 - in the absence of Mo, apoprotein concentration was about half the amount of maximally induced nitrate reductase. Cycloheximide stabilised preformed nitrate reductase which disappeared steadily in the presence of puromycin. Apoprotein was not stabilised by either antimetabolite.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1573-5036
    Keywords: Acetone ; Ammonium ; Cauliflower ; Denitrification ; Nitrate ; Nitrate reductase ; Nitrification ; N loss ; N recovery ; N-Serve ; Radish ; Turnip ; Urea
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary N-serve (2-chloro-6-(trichloromethyl)pyridine) was tested as an inhibitor of nitrification of ammonium or urea in sand cultures. Nitrification was reduced but not prevented by N-Serve present at between 5 and 20 ppm in solution or by weight of sand. In the presence of root debris and acetone, used in some experiments at 2–4 ml/l of nutrient to convey N-Serve, denitrification was stimulated under the same conditions and resulted in loss of a large proportion of nitrate, probably mainly as gaseous products and some nitrite. These losses were greater when N-serve was also present. There was also conversion of nitrate to an insoluble form in the sand. A smaller proportional loss of nitrate occurred in other treatments in the presence of root debris when N-Serve was added without acetone, either as the commercial formulation 24E or as a solid. Thus, using N-Serve to inhibit nitrification may encourage denitrifying organisms especially in the presence of carbon sources including root debris or acetone. Large decreases of nitrate reductase activity in plants produced by using N-Serve in the presence of ammonium or urea were caused as much by losses of nitrate in the presence of acetone as by prevention of nitrate formation. Other N-Serve treatments (solid or 24E) decreased enzyme induction by between 50 and 90 per cent as a result mainly of reduced nitrification.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...