FTIR spectroscopy was used to investigate the effects of extremely low frequency (50？Hz) electromagnetic field and of microwaves at 900？MHz on the secondary structure of a typical protein, the lysozyme, evaluating the bioprotective effectiveness of trehalose. Lysozyme in D2O solution (60？mg/ml) was exposed to 50？Hz frequency electromagnetic field at 180？μT. The FTIR spectra indicated an increase of CH2 group at 1921 and 1853？cm？1 after 3？h of exposure. Such effect was not observed after the addition of trehalose (150？mg/mL) at the same exposure conditions. Lysozyme dissolved in D2O at the concentration of 100？mg/mL was exposed up to 4？h to 900？MHz mobile phone microwaves at 25？mA/m. A significant increase in intensity of the amide I vibration band in the secondary structure of the protein was observed after 4？h exposure to microwaves. This effect was inhibited by the presence of trehalose at the concentration of 150？mg/mL. Fourier self-deconvolution spectral analysis of lysozyme in D2O solution after exposure to microwaves revealed an increase in intensity of the conformational components of amide I mode, particularly of β-sheet and turn that can be attributed to disorder and unfolding processes of the protein. 1. Introduction The aim of this work is to investigate the effects of the environmental electromagnetic fields on the secondary structure of hydrated lysozyme in absence and in the presence of the disaccharide trehalose. Proteins are fundamentals in organic metabolism of livings. In the cells each protein must fold into the specific conformational state in a complex and highly crowded environment, and the folding process is aided by a range of auxiliary proteins [1, 2]. Lysozyme (LYS) is a residue protein found in secretions (e.g., saliva, sweat, and mucus) and more generally in leukocytes and kidneys. Epidemiological studies carried out up to now evidenced a relationship between an increase of risk of cancer and the exposure to extremely low frequency electromagnetic field (ELF-EMF) [3] and to radiofrequencies and microwaves (RF-MWs) [4]. In response to public concern over health effects of EMF exposure, in 1996, the International EMF Project was established by WHO and the Radiation and Environmental Health Unit, which coordinated studies on EMF relative to the Environmental Health Criteria (EHC), whose main objective was to review the scientific literature on the biological effects of exposure to ELF-EMF fields to assess any health risks from exposure to these fields. In particular, the International Agency for Research on Cancer (IARC)
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