Δ1-pyrroline-5-carboxylate reductase as a new target for therapeutics: inhibition of the enzyme from Streptococcus pyogenes and effects in vivo.

Compounds able to interfere with amino acid biosynthesis have the potential to inhibit cell growth. In both prokaryotic and eukaryotic microorganisms, unless an ornithine cyclodeaminase is present, the activity of δ1-pyrroline-5-carboxylate (P5C) reductase is mandatory to proline production, and the enzyme inhibition should result in amino acid starvation, blocking in turn protein synthesis. The ability of some substituted derivatives of aminomethylenebisphosphonic acid and its analogues to interfere with the activity of the enzyme from the human pathogen Streptococcus pyogenes was investigated. Several compounds were able to suppress activity in the micromolar range of concentrations, with a mechanism of uncompetitive type with respect to the substrate P5C and non-competitive with respect to the electron donor NAD(P)H. The actual occurrence of enzyme inhibition in vivo was supported by the effects of the most active derivatives upon bacterial growth and free amino acid content.

Ceftolozane/Tazobactam and Ceftazidime/Avibactam for Multidrug-Resistant Gram-Negative Infections in Immunocompetent Patients: A Single-Center Retrospective Study.

Complicated infections from multidrug-resistant Gram-negative bacteria (MDR-GNB) represent a serious problem presenting many challenges. Resistance to many classes of antibiotics reduces the probability of an adequate empirical treatment, with unfavorable consequences, increasing morbidity and mortality. Readily available patient medical history and updated information about the local microbiological epidemiology remain critical for defining the baseline risk of MDR-GNB infections and guiding empirical treatment choices, with the aim of avoiding both undertreatment and overtreatment. There are few literature data that report real-life experiences in the use of ceftolozane/tazobactam and ceftazidime/avibactam, with particular reference to microbiological cure. Some studies reported experiences for the treatment of MDR-GNB infections in patients with hematological malignancies or specifically in Pseudomonas aeruginosa infections. We report our clinical single-center experience regarding the real-life use of ceftolozane/tazobactam and ceftazidime/avibactam to treat serious and complicated infections due to MDR-GNB and carbapenem-resistant Enterobacterales (CRE), with particular regard given to intra-abdominal and urinary tract infections and sepsis.

Biocide activity of microfiber mops with and without silver after contamination.

OBJECTIVE: The purpose of the present research was to compare the residual microbial load in Solo System microfiber mops with silver and in normal microfiber mops without silver to see whether those with the silver prevent bacterial proliferation and spread more effectively during normal cleaning operations. METHODS: Mops with and without silver were experimentally contaminated with suspension of Staphylococcus aureus ATCC 6538. The bioburden was evaluated by a filtering procedure according to UNI EN 1174 after contamination, after washing and after different times of impregnation in an alcohol-base detergent. RESULTS AND DISCUSSION: The results obtained lead to the conclusion that silver microfiber mop was significantly more effective in reducing bacterial load despite initial high level contamination (106-107 CFU/50 cm²). Indeed, after low temperature washing, the bacterial load was already completely eliminated while the mop without silver still presented relatively high levels of the microorganism (approximately 10² CFU/50 cm²) even after being soaked for 8 hours in a detergent/disinfectant.

Biocide activity of microfiber mops with and without silver after contamination

OBJECTIVE: The purpose of the present research was to compare the residual microbial load in Solo System microfiber mops with silver and in normal microfiber mops without silver to see whether those with the silver prevent bacterial proliferation and spread more effectively during normal cleaning operations. METHODS: Mops with and without silver were experimentally contaminated with suspension of Staphylococcus aureus ATCC 6538. The bioburden was evaluated by a filtering procedure according to UNI EN 1174 after contamination, after washing and after different times of impregnation in an alcohol-base detergent. RESULTS AND DISCUSSION: The results obtained lead to the conclusion that silver microfiber mop was significantly more effective in reducing bacterial load despite initial high level contamination (10(6)-10(7) CFU/50 cm²). Indeed, after low temperature washing, the bacterial load was already completely eliminated while the mop without silver still presented relatively high levels of the microorganism (approximately 10² CFU/50 cm²) even after being soaked for 8 hours in a detergent/disinfectant.