Microbial nickel: cellular uptake and delivery to enzyme centers

Area of Science:

• Microbiology
• Biochemistry
• Enzymology

Background:

• Nickel enzymes are crucial for microbial survival and virulence, enabling unique biochemical processes.
• Accessing and delivering nickel ions to enzyme active sites is a complex cellular challenge.

Purpose of the Study:

• To review recent advancements in understanding nickel ion import and delivery systems in microorganisms.
• To elucidate the mechanisms by which nickel ions are incorporated into essential nickel enzymes.

Main Methods:

• Review of current literature on nickel transport systems (e.g., TonB-dependent, ABC-type transporters).
• Analysis of nickel metallochaperone proteins and maturation factors involved in nickel enzyme production.
• Examination of small molecules, such as L-histidine, involved in nickel chelation and transport.

Main Results:

• Nickel ions are chelated by small molecules like L-histidine before transport across cell membranes.
• Specialized outer-membrane and inner-membrane transporters facilitate nickel ion import.
• Maturation factors and metallochaperones ensure selective delivery and incorporation of nickel into enzymes like [NiFe]-hydrogenase, urease, and lactate racemase.

Conclusions:

• Microbial nickel acquisition involves sophisticated import and delivery pathways.
• Understanding these nickel trafficking systems enhances knowledge of microbial metabolism, survival, and pathogenesis.
• Further research into these pathways can reveal novel targets for antimicrobial strategies.