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In the present work, metallomics studies using biomolecular (matrix-assisted laser desorplion ionization timeof-flight tandem mass spectrometiy, MALDI-TOF MS/MS) and elemental mass spectrometly (laser ablation inductively coupled plasma mass spectrometly, LA-ICPMS) of human blood serum samples from bipolar disorder (liD) patients compared to controls were performed. The serum samples from three different groups: control (n = 25), BD patients treated with Li (n = 15), and BD patients not treated with Ii (n = 10), were pooled according to their groups and separated by two-dimensional polyacrylamide gel electrophoresis (2-fl PAGE). Then, in order to determine the metals bound to the protein spots and search for differences among the studied groups, the 2-fl gels were analyzed by LA-ICPMS in three distinct modes: bioimaging of metals in gel sections, line scan through the protein spots, and microlocal analysis of selected protein spots. MALDI-TOF MS/MS characterized 32 serum proteins, and they were associated with the metals previously detected. When comparing control and treated BD patient groups, a differentiation in terms of metals bound to proteins was possible to observe. The main metals bound to proteins found in all groups were Na, Mg, Th, Ca, and Fe. Mn was only detected in the control group; Co was only observed in the control and BD patients treated with Li group. K and Ti were only found in the BD patient groups, and P was only observed in control and BD patients not treated with Li drugs. This exploratory work shows that the association of IA-ICPMS with MAUM-TOF MS/MS is a powerful strategy in metallomics studies applied to determine differences in metal-containing proteins, being able to play an important role on the discovery of potential markers for BD and its treatment with Li in serum samples. [ABSTRACT FROM AUTHOR]

The cytoplasmic, NAD-linked hydrogenase of the Gram-positive hydrogen-oxidizing bacterium Nocardia opaca 1b was compared with the analogous enzyme isolated from the Gram-negative bacterium Alcaligenes eutrophus H16. The hydrogenase of N. opaca 1b was purified by a new procedure applying chromatography on phenyl-Sepharose and DEAE-Sephacel with two columns in series. A homogeneous enzyme preparation with a specific activity of 74 µmol H2 oxidized · min-1 · mg protein-1 and a yield of 32% was isolated. The A. eutrophus enzyme was purified as previously published. Both enzymes are tetrameric proteins composed of four nonidentical subunits (α, β, γ, δ). The four subunits of both of these enzymes were separated and isolated as single polypeptides by preparative polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. Immunological comparison of the four subunits of the Nocardia hydrogenase with those of the Alcaligenes enzyme showed that the α, β, δ, and δ subunits of one organism were serologically related to the analogous subunits of the other organism. Among themselves, the four subunits do not have any serological relationship. The eight individual polypeptides were also compared with respect to the NH2-terminal amino acid sequences determined by automated Edman degradation and to the amino acid compositions. Strong sequence similarities exist between the analogous subunits isolated from the two bacteria. Within the established N-terminal sequences the similarities between both α, β, γ and δ subunits amount to 63%, 79%, 80% and 65%, respectively. No similarities exist between the different, non-analogous subtmits α, β, γ and δ. [ABSTRACT FROM AUTHOR]