Rapid characterization of microorganisms by mass spectrometry--what can be learned and how?

Strategies for the rapid and reliable analysis of microorganisms have been sought to meet national needs in defense, homeland security, space exploration, food and water safety, and clinical diagnosis. Mass spectrometry has long been a candidate technique because it is extremely rapid and can provide highly specific information. It has excellent sensitivity.

Evidence for operation of the direct zinc ligand exchange mechanism for trafficking, transport, and reactivity of zinc in mammalian cells.

In addition to its critical role in normal cell function, growth, and metabolism, zinc is implicated as a major factor in the development and progression of many pathological conditions and diseases. Despite this importance of zinc, many important factors, processes, and mechanisms of the physiology, biochemistry, and molecular biology of zinc remain unknown. Especially important is the unresolved issue regarding the mechanism and process of the trafficking, transport, and reactivity of zinc in cells; especially in mammalian cells.

Allosteric signaling in the biotin repressor occurs via local folding coupled to global dampening of protein dynamics.

The biotin repressor is an allosterically regulated, site-specific DNA-binding protein. Binding of the small ligand bio-5'-AMP activates repressor dimerization, which is a prerequisite to DNA binding. Multiple disorder-to-order transitions, some of which are known to be important for the functional allosteric response, occur in the vicinity of the ligand-binding site concomitant with effector binding to the repressor monomer.

Quantitative determination of heme for forensic characterization of bacillus spores using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

A quantitative method was developed for the determination of heme (ferriprotoporphyrin IX) using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS). The method was designed for forensic characterization of the use of blood agar in preparation of Bacillus spores. An alkali wash of 0.