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The cyanobacterium Thermosynechococcus elongatus is one the few bacteria to possess two Dps proteins, DpsA-Te and Dps-Te. The present characterization of DpsA-Te reveals unusual structural and functional features that differentiate it from Dps-Te and the other known Dps proteins. Notably, two Zn(II) are bound at the ferroxidase center, owing to the unique substitution of a metal ligand at the A-site (His78 in place of the canonical aspartate) and to the presence of a histidine (His164) in place of a hydrophobic residue at a metal-coordinating distance in the B-site. Only the latter Zn(II) is displaced by incoming iron, such that Zn(II)-Fe(III) complexes are formed upon oxidation, as indicated by absorbance and atomic emission spectroscopy data. In contrast to the typical behavior of Dps proteins, where Fe(II) oxidation by H(2)O(2) is about 100-fold faster than by O(2), in DpsA-Te the ferroxidation efficiency of O(2) is very high and resembles that of H(2)O(2). Oxygraphic experiments show that two Fe(II) are required to reduce O(2), and that H(2)O(2) is not released into solution at the end of the reaction. On this basis, a reaction mechanism is proposed that also takes into account the formation of Zn(II)-Fe(III) complexes. The physiological significance of the DpsA-Te behavior is discussed in the framework of a possible localization of the protein at the thylakoid membranes, where photosynthesis takes place, with the consequent increased formation of reactive oxygen species.

Aims: To determine the ability of probiotic lactobacilli to improve the treatment of vulvovaginal candidiasis (VVC) using a randomized, double-blind and placebo-controlled trial. Methods and Results: Fifty-five women diagnosed with VVC by vaginal discharge positive for Candida spp. (according to culture method) associated with at least one of the symptoms (itching and burning vaginal feeling, dyspareunia and dysuria), were treated with single dose of fluconazole (150 mg) supplemented every morning for the following 4 weeks with two placebo or two probiotic capsules (containing Lactobacillus rhamnosus GR-1 and Lactobacillus reuteri RC-14). At 4 weeks, the probiotic treated group showed significantly less vaginal discharge associated with any of the above mentioned symptoms (10·3%vs 34·6%; P = 0·03) and lower presence of yeast detected by culture (10·3%vs 38·5%; P = 0·014). Conclusion: This study has shown that probiotic lactobacilli can increase the effectiveness of an anti-fungal pharmaceutical agent in curing disease. Significance and Impact of the Study: This novel finding of probiotic lactobacilli augmenting the cure rate of yeast vaginitis, not only offers an alternative approach to a highly prevalent condition that adversely affects the quality of life of women around the world, but also raises the question of how this combination works. © 2009 The Society for Applied Microbiology.

Naturalis® is a bioinsecticide based on living conidiospores of the naturally occuring Beauveria bassiana strain ATCC 74040. The entomopathogenic fungus acts primarily by contact: once attached to the insect’s cuticle, the conidiospores germinate producing penetration hyphae, which enter and proliferate inside the insect’s body. The fungus invades and feeds on its host, causing its death due to dehydration and/or depletion of nutrients. Several years of laboratory, semi-field and field studies showed that also Tephritid flies (Ceratitis capitata, Rhagoletis cerasi, Bactrocera oleae) are susceptible to infection by B. bassiana strain ATCC 74040. The results of efficacy trials conducted in 2004-05 are reported. Naturalis was tested both alone and in an integrated pest management strategy. The product showed high efficacy in controlling R. cerasi, comparable to or higher than that of the chemical reference treatment. The B. bassiana-based product Naturalis can thus be considered an efficient tool for the control of the cherry fruit fly.

DNA-binding proteins from starved cells (Dps proteins) protect bacteria primarily from oxidative damage. They are composed of 12 identical subunits assembled with 23-symmetry to form a compact cage-like structure known to be stable at temperatures > 70 degrees C and over a wide pH range. Thermosynechococcus elongatus Dps thermostability is increased dramatically relative to mesophilic Dps proteins. Hydrophobic interactions at the dimeric and trimeric interfaces called Dps-like are replaced by salt bridges and hydrogen bonds, a common strategy in thermophiles. Moreover, the buried surface area at the least-extended Dps-like interface is significantly increased. A peculiarity of T. elongatus Dps is the presence of a chloride ion coordinated with threefold symmetry-related arginine residues lining the opening of the Dps-like pore toward the internal cavity. T. elongatus Dps conserves the unusual intersubunit ferroxidase centre that allows the Dps protein family to oxidize Fe(II) with hydrogen peroxide, thereby inhibiting free radical production via Fenton chemistry. This catalytic property is of special importance in T. elongatus (which lacks the catalase gene) in the protection of DNA and photosystems I and II from hydrogen peroxide-mediated oxidative damage.

Metabolic, hormonal and vascular disorders are considered to cause hearing dysfunction such as progressive sensorineural hearing loss (PSNHL). The diseases most commonly associated with PSNHL are diabetes mellitus, congenital and acquired hypothyroidism, chronic renal failure, chronic labyrinthine ischemia determined by non-hematologic factors (tissue perfusion pressure, blood vessel diameter) or by hematologic factors (blood viscosity and/or rigidity of the red blood cells). In this study a review of data on the relationship between these clinical disorders and the presence and deterioration of the hearing function was carried out. PSNHL seems to be significantly associated with diabetes mellitus, in particular the mitochondrial type: a progressive deterioration of the hearing function is reported in 60% of the patients suffering from this type of disease with mitochondrial mutations. Regarding hypothyroid disorders, the data do not support a pathogenetic link between PSNHL and acquired hypothyroidism, whereas in subjects with congenital hypothyroidism both clinical and experimental results indicate a progressive damage of hearing function if the thyroid disorder is not treated early in life. Also, in patients with chronic renal failure the hearing thresholds seem to be significantly worse than in control subjects, particularly in patients undergoing dialysis, whereas the effect of kidney transplantation on auditory function is still not understood. Finally a relationship between PSNHL and chronic labyrinthine ischemia due to alterations of hematologic factors (increase of blood viscosity and/or increase of rigidity of the red blood cells) has been reported by several authors. However, data on high blood pressure and hyperlipoproteinemia as causes of deterioration of hearing acuity are controversial, and it is often difficult to understand whether the progressive hearing deficit is due only to these factors or also to the elderly age of patients.