Related Experiment Videos
A novel transporter involved in cobalt uptake
H Komeda1, M Kobayashi, S Shimizu
1Department of Agricultural Chemistry, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Japan.
Summary
Researchers discovered a new gene, nhlF, crucial for cobalt transport in Rhodococcus rhodochrous J1. This gene, encoding the NhlF protein, facilitates energy-dependent cobalt uptake, essential for nitrile hydratase (L-NHase) enzyme activity.
Area of Science:
- Microbiology
- Biochemistry
- Molecular Biology
Background:
- Cobalt is vital for the low molecular-mass nitrile hydratase (L-NHase) in Rhodococcus rhodochrous J1.
- Nitrile degradation involves L-NHase and amidase enzymes.
Purpose of the Study:
- Identify novel genes involved in cobalt acquisition for L-NHase.
- Characterize the function and transport mechanism of the newly identified NhlF protein.
Main Methods:
- Gene cloning and expression in Rhodococcus rhodochrous and Escherichia coli.
- Radioisotope uptake assays using 57Co and 63Ni.
- Bioinformatic analysis including sequence similarity and hydropathy plots.
- Enzyme activity assays and effects of uncouplers.
Main Results:
- A new gene, nhlF, was identified adjacent to L-NHase and amidase genes.
- The NhlF protein shares similarity with known nickel transport proteins but mediates cobalt uptake.
- Expression of nhlF confers energy-dependent cobalt uptake, enhancing L-NHase activity.
- Cobalt uptake was inhibited by uncouplers, indicating an energy-dependent process.
Conclusions:
- NhlF is a novel cobalt transporter essential for L-NHase function in Rhodococcus rhodochrous.
- The NhlF protein plays a critical role in cellular cobalt homeostasis.
- Understanding cobalt transport mechanisms can inform biotechnological applications involving metalloenzymes.