A role for microbial selection in frescoes' deterioration in Tomba degli Scudi in Tarquinia, Italy

Mural paintings in the hypogeal environment of the Tomba degli Scudi in Tarquinia, Italy, show a quite dramatic condition: the plaster mortar lost his cohesion and a white layer coating is spread over almost all the wall surfaces. The aim of this research is to verify if the activity of microorganisms could be one of the main causes of deterioration and if the adopted countermeasures (conventional biocide treatments) are sufficient to stop it. A biocide treatment of the whole environment has been carried out before the conservative intervention and the tomb has been closed for one month. When the tomb was opened again, we sampled the microorganisms present on the frescoes and we identified four Bacillus species and one mould survived to the biocide treatment. These organisms are able to produce spores, a highly resistant biological form, which has permitted the survival despite the biocide treatment. We show that these Bacillus strains are able to produce calcium carbonate and could be responsible for the white deposition that was damaging and covering the entire surface of the frescoes. Our results confirm that the sanitation intervention is non always resolutive and could even be deleterious in selecting harmful microbial communities

Annurca apple (M. pumila Miller cv Annurca) extracts act against stress and ageing in S. cerevisiae yeast cells

During the past years, a number of studies have demonstrated the positive effect of apple on ageing and different diseases such as cancer, degenerative and cardiovascular diseases. The unicellular yeast Saccharomyces cerevisiae represents a simple eukaryotic model to study the effects of different compounds on lifespan. We previously demonstrated that apple extracts have anti-ageing effects in this organism because of their antioxidant properties. In particular, the effect is related to the presence in this fruit of polyphenols, which give a large contribution to the antioxidant activity of apples

New perspectives from South-Y-East, not all about death. A report of the 12lnternational Meeting on Yeast Apoptosis in Bari, Italy, May 14th-18th, 2017

Over the last 14 years, the field of yeast regulated cell death (RCD) has been expanding to more and more biomedical research themes, including aging, human diseases, cell stress response, metabolism and systems biology. The 12th International Meeting on Yeast Apoptosis (IMYA12), which was held in Bari, Italy from May 14th to 18th, 2017, nicely reflected this trend. This year, more than 100 participants, among which senior and young scientists from Europe, USA, North Africa and Japan, had an intense and open exchange of achievements and ideas. This open and informal communication among researchers has been a constant hallmark of all the IMYA meetings. The global yeast death community was embraced and inspired by the lively and warm atmosphere of Bari, the capital city of Apulia, and its beautiful surroundings, with colorful landscapes, historical and artistic heritage, tastes and scents that reflect the interface between Eastern and Western culture

Increased levels of RNA oxidation enhance the reversion frequency in aging pro-apoptotic yeast mutants

Despite recent advances in understanding the complexity of RNA processes, regulation of the metabolism of oxidized cellular RNAs and the mechanisms through which oxidized ribonucleotides affect mRNA translation, and consequently cell viability, are not well characterized. We show here that the level of oxidized RNAs is markedly increased in a yeast decapping Kllsm4Δ1 mutant, which accumulates mRNAs, ages much faster that the wild type strain and undergoes regulated-cell-death. We also found that in Kllsm4Δ1 cells the mutation rate increases during chronological life span indicating that the capacity to han- dle oxidized RNAs in yeast declines with aging. Lowering intracellular ROS levels by antioxidants recovers the wild- type phenotype of mutant cells, including reduced amount of oxidized RNAs and lower mutation rate. Since mRNA oxidation was reported to occur in different neurodegen- erative diseases, decapping-deficient cells may represent a useful tool for deciphering molecular mechanisms of cell response to such conditions, providing new insights into RNA modification-based pathogenesis

mRNA degradation and its effect on cellular lifespan and apoptosis in yeast

The steady-state level of cellular mRNA is the result of the equilibrium between the rates of synthesis and decay. For this reason, the control of mRNA degradation is an important element in regulation of gene expression. In all eukaryotes, the decay of mRNAs usually starts with the removal of the 3′ end poly(A) tail. In the principal degradation pathway in the yeast S. cerevisiae, deadenylation is followed by decapping and by 5′ to 3′ mRNA degradation by the exonuclease Xrn1. mRNA decay can be also carried out in the opposite direction by the exosome, a complex with a 3′ to 5′ nuclease activity. We previously reported that yeast mutants in genes of the mRNA decapping pathway show premature aging and undergo apoptosis by a YCA1-dependent pathway. These traits are accompanied by elevated histone mRNA levels persisting throughout the cell cycle and defects in S-phase progression. Analyzing the data concerning the negative genetic interactions of specific genes, as well those obtained with genome wide analysis, we found that gene mutants that are lethal/sick with lsm genes can be clustered in functional groups such as histone/chromatine modifications, protein translation, DNA replication/repair, nuclear mRNA export, mitochondrial function/biogenesis and autophagy. We are currently studying the role of these pathways in cellular aging and apoptosis

mRNA degradation and its effect on cellular lifespan and apoptosis in yeast

The control of mRNA degradation is an important element in regulation of gene expression. In all eukaryotes, the decay of mRNAs usually starts with the removal of the 3′ end poly(A) tail. In the principal degradation pathway in the yeast S. cerevisiae, deadenylation is followed by decapping and by 5′ to 3′ mRNA degradation by the exonuclease Xrn1. We previously reported that yeast mutants in genes of the mRNA decapping pathway show premature aging and undergo programmed cell death. These traits are accompanied by elevated histone mRNA levels persisting throughout the cell cycle and defects in S-phase progression. Analyzing the data concerning the negative genetic interactions of specific genes, as well those obtained with genome wide analysis, we found that gene mutants that are lethal/sick with lsm genes can be clustered in functional groups such as histone/chromatine modifications, protein translation, DNA replication/repair, nuclear mRNA export, mitochondrial function/biogenesis and autophagy. We are currently studying the role of these pathways in cellular aging and apoptosis related to mRNA turn over

Role of GABA metabolism enzymes during stress, aging and apoptosis in budding yeast, Saccharomyces cerevisiae

The γ-aminobutyric acid (GABA) is a non-proteic aminoacid synthesized by almost all living organisms. GABA metabolism, known as “GABA shunt” involves three enzymes: glutamate decarboxylase (GAD), GABA aminotransferase (GAT) and succinate semialdehyde dehydrogenasi (SSADH). These three enzymes act in concert to convert glutamate (α-ketoglutarate) to succinate, bypassing two reactions of the tricarboxylic acid cycle. The GABA shunt pathway is well conserved from bacteria, fungi and plants through vertebrates with different biological function in each organism [1] [2]. In mammals, GABA has two different roles: inhibitory neurotransmitter and trophic factor during central nervous system (CNS) development. In plants, the GABA shunt appears to contribute to the control of cytosolic pH, balance between carbon and nitrogen metabolism and to stress response. In some of enteric bacteria GABA is a metabolic product inside the cell and it is involved in acid resistance system. GABA has also been shown to play a potential signalling role in biological and developmental processes, i.g. it has been found as signalling molecule during host-pathogen interactions and during yeast colony development [3]. In the yeast Saccharomyces cerevisiae, the deletion of UGA3 gene -which encodes a zinc-finger transcription factor necessary for GABA-dependent induction of the UGA1 (GABA aminotransferase), UGA2 (succinate semialdehyde dehydrogenase), and UGA4 (GABA permease) genes- extends replicative lifespan, as did deletion of UGA1 and GAD1 (glutamate decarboxylase); in contrast strains with UGA2 or UGA4 deletions exhibited no lifespan extensions. Therefore, two genes in the GABA metabolism pathway, UGA1 and GAD1, were identified as aging genes. [1]. Nevertheless, the effects of these enzymes on chronological lifespan and stress response have not been studied yet. Data on the role of GABA shunt in budding yeast during CLS and under stress conditions will be presented. References: [1] Cao J., Barbosa J.M., Singh N.K. and Locy R.D. (2013), Yeast, (4):129-44. [2] Kamei Y., Tamura T., Yoshida R., Ohta S., Fukusaki E. and Mukai Y. (2011), Biochem Biophys Res Commun, 407(1):185-90. [3] Cáp M, Stěpánek L, Harant K, Váchová L, Palková Z. (2012), Mol Cell. 25;46(4):436-4

Prüfung der bakteriziden Wirksamkeit eines thermischen “Lanzeitdesinfektionsgeräts

Gli AA. hanno valutato l'efficacia battericida di un asettizzatore termico a ciclo lungo. Stabilita la sterilità del liquido contenente le lenti sigillate, queste sono state contaminate in soluzioni contenenti 108 batteri/ml selezionati da soggetti portatori. Le lenti sottoposte a trattamento termico a ciclo lungo si sono rilevate sterili mentre le altre non trattate hanno evidenziato la crescita di innumerevoli colonie batteriche

Neue Methodik für die quantitative Bewertung der Reinigungswirkung von enzymatischen Lösungen

Gli AA. sfruttando la capacità di legame della clorexidina con le proteine del film lacrimale, hanno messo a punto una metodica per valutare l'efficacia di più sistemi pulenti. Tale metodica è stata impiegata per studiare alcune soluzioni enzimatiche presenti sul mercato. I risultati negativi ottenuti hanno fatto ipotizzare che sia necessario, fino a prova contraria, far seguire alla pulizia con enzimi una con tensioattivi, che non si ha una perfetta conoscenza del programma di azione degli enzimi in soluzione e che non sono ancora ben note le reazioni degli enzimi con gli altri prodotti chimici impiegati