Molecular Physiology of Metal-Microbe Interactions According to Mechanisms -- Understanding How Cells Allocate Metals -- Metalloregulators: Arbiters of Metal Sufficiency -- Transcriptomic Responses of Bacterial Cells to Sublethal Metal Ion Stress -- Bacterial Transition Metal Homeostasis -- Biosensing of Heavy Metals -- A Glossary of Microanalytical Tools to Assess the Metallome -- Molecular Physiology of Metal-Microbe Interactions According to Groups -- Acquisition of Iron by Bacteria -- New Transport Deals for Old Iron -- Manganese: Uptake, Biological Function, and Role in Virulence -- How Bacteria Handle Copper -- Microbial Physiology of Nickel and Cobalt -- Zinc, Cadmium, and Lead Resistance and Homeostasis -- Microbiology of the Toxic Noble Metal Silver -- Mercury Microbiology: Resistance Systems, Environmental Aspects, Methylation, and Human Health -- Arsenic Metabolism in Prokaryotic and Eukaryotic Microbes -- Reduction and Efflux of Chromate by Bacteria -- Molybdate and Tungstate: Uptake, Homeostasis, Cofactors, and Enzymes. All forms of life depend on a variety of heavy metal ions. Nearly one-third of all gene products require a metal ion for proper folding or function. However, even metals generally regarded as non-poisonous are toxic at higher concentrations, including the essential ones. Thus, sensitive regulation of metal uptake, storage, allocation and detoxification is needed to maintain cellular homeostasis of heavy metal ions. Molecular Microbiology of Heavy Metals includes chapters on allocation of metals in cells, metal transporter, storage and metalloregulatory proteins, cellular responses to metal ion stress, transcription of genes involved in metal ion homeostasis, uptake of essential metals, metal efflux and other detoxification mechanisms. Also discussed are metal bioreporters for the nanomolar range of concentration and tools to address the metallome. Chapters in the second part cover specific metals such as Fe, Mn, Cu, Ni, Co, Zn and Mo as key nutrient elements and Ag, As, Cd, Hg and Cr as toxic elements.