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Journal Article
Ultrasonic assisted protein enzymatic digestion for fast protein identification by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry Sonoreactor versus ultrasonic probe, Rial-Otero, R., Carreira R. J., Cordeiro F. M., Moro A. J., Santos H. M., Vale G., Moura I., and Capelo J. L. , Journal of Chromatography A, Sep 28, Volume 1166, Number 1-2, p.101-107, (2007) AbstractWebsite

Two different ultrasonic energy sources, the sonoreactor and the ultrasonic probe, are compared for enzymatic digestion of proteins for protein identification by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDl-TOF-MS) using the peptide mass fingerprint (PMF) procedure. Variables such as (i) trypsin/protein ratio; (ii) sonication time; (iii) ultrasound amplitude; and (iv) protein concentration are studied and compared. As a general rule, the trypsin/protein ratio and the minimum protein concentration successfully digested are similar with both ultrasonic energy sources. Results showed that the time needed to digest proteins was shorter with the ultrasonic probe, 60 s versus 120 s, for the same amplitude of sonication, 50%. However, lower standard deviations and cleaner MALDI-TOF-MS spectra were obtained with the sonoreactor. In addition, the sonoreactor device provided higher sample throughput (6 samples for the sonoreactor versus 1 sample for the ultrasonic probe) and easier sample handling for lower sample volumes (25 mu l). Finally, a comparison of both methodologies for the specific identification of the adenylylsulphate reductase alfa subunit from a complex protein mixture from Desulfovibrio desulfuricans ATCC 27774 was done as a proof of the procedure. (c) 2007 Elsevier B.V. All rights reserved.

Ultrasonic multiprobe as a new tool to overcome the bottleneck of throughput in workflows for protein identification relaying on ultrasonic energy, Santos, H. M., Carreira R., Diniz M. S., Rivas M. G., Lodeiro C., Moura J. J., and Capelo J. L. , Talanta, Apr 15, Volume 81, Number 1-2, p.55-62, (2010) AbstractWebsite

We studied in this work the performance of the new ultrasonic multiprobe in terms of throughput, handling and robustness. The study was conducted using the multiprobe to speed two different proteomics workflows. The "classic" method relaying on overnight protein digestion (12h), was used as the standard procedure. This work clearly shows the importance of testing variables such as ultrasonic amplitude and ultrasonic time when adapting an ultrasonic-based treatment to a new ultrasonic device. The results here presented also shown and confirm the advantage of speed up sample treatment workflows with the aid of ultrasonic energy in combination with a 96-well plate. The methods compared were similar in terms of robustness, but the desalting free method was the fastest, requiring only 2 min/sample for completion. In addition it was also the simplest in terms of handling, since no desalting step was needed. The following standard proteins were successfully identified using the methods studied: bovine serum albumin, alpha-lactalbumin, ovalbumin, carbonic anhydrase, fructose-bisphosphate aldolase A, catalase, chymotrypsinogen A. As case study, the identification of the protein Split-Soret cytochrome c from D. desulfuricans ATCC 27774 was carried out.

Unambiguous identification of the nickel EPR signal in 61Ni-enriched Desulfovibrio gigas hydrogenase, Moura, J. J., Moura I., Huynh B. H., Kruger H. J., Teixeira M., DuVarney R. C., Dervartanian D. V., Xavier A. V., Peck, H. D. Jr., and Legall J. , Biochem Biophys Res Commun, Oct 29, Volume 108, Number 4, p.1388-93, (1982) AbstractWebsite
Understanding the response of Desulfovibrio desulfuricans ATCC 27774 to different electron acceptors - biosynthetic costs modulate substrate selection, Sousa, J. R., Silveira C. M., Fontes P., Roma-Rodrigues C., Fernandes A. R., Van Driessche G., Devreese B., Moura I., Moura J. J. G., and Almeida M. G. , Biochim Biophys Acta, Volume 1865, p.1455-1469, (2017)
Unusual reduction mechanism of copper in cysteine-rich environment, Maiti, B. K., Maia L., Moro A. J., Lima J. C., Cordas C., Moura I., and Moura J. J. G. , Inorg Chem, Volume 57, p.8078-8088, (2018) Website
Using cytochrome c(3) to make selenium nanowires, Abdelouas, A., Gong W. L., Lutze W., Shelnutt J. A., Franco R., and Moura I. , Chemistry of Materials, Jun, Volume 12, Number 6, p.1510-+, (2000) AbstractWebsite

We report on a new method to make nanostructures in aqueous solution at room temperature. We used the protein cytochrome c(3) to catalyze reduction of selenate (SeO42-) to selenium Se-0 by dithionite. Reduction was instantaneous. After a week spherical nanoparticles of red Se-0 (about 50 nm diameter) precipitated, followed by self-assembling into crystalline nanowires, typically 1 mu m long. The nanowires were composed of one strand of spherical particles; thicker strands contained several nanoparticles in parallel.