Related Experiment Videos
Molybdenum uptake in Escherichia coli K12
G Lopez Corcuera1, M Bastidas, M Dubourdieu
1Universidad de Los Andes, Facultad de Ciencias, Departamento de Biología, Mérida, Venezuela.
Journal of General Microbiology
|August 1, 1993
Summary
Escherichia coli K12 utilizes an active transport system for molybdenum uptake, involving a periplasmic binding protein. A specific chlD strain shows altered molybdenum processing, allowing for its removal from cells.
Area of Science:
- Microbiology
- Molecular Biology
- Biochemistry
Background:
- Molybdenum is an essential trace element for many enzymes.
- Understanding molybdenum transport in bacteria like Escherichia coli is crucial for metabolic studies.
Purpose of the Study:
- To characterize the molybdenum uptake system in Escherichia coli K12.
- To investigate the role of the chlD mutation in molybdenum processing.
Main Methods:
- Utilized the radionuclide 99Mo to trace molybdenum uptake.
- Analyzed molybdenum uptake kinetics and inhibition patterns.
- Detected molybdate binding protein activity in periplasmic fluid.
Main Results:
- Molybdenum uptake exhibited biphasic kinetics, indicating active transport.
- The chlD strain showed altered subsequent molybdenum processing compared to wild-type.
- Uptake was energy-dependent, pH-sensitive, and involved a periplasmic binding protein.
Conclusions:
- Molybdate transport in E. coli K12 is an energy-dependent, periplasmic binding protein system.
- The chlD mutation affects intracellular molybdenum processing rather than initial uptake.
- A molybdate binding protein with high affinity (KD of 9 nM) was identified.