Papers by Claudia Sorlini
Your article is protected by copyright and all rights are held exclusively by Springer-Verlag and... more Your article is protected by copyright and all rights are held exclusively by Springer-Verlag and the University of Milan. This e-offprint is for personal use only and shall not be selfarchived in electronic repositories. If you wish to self-archive your work, please use the accepted author's version for posting to your own website or your institution's repository. You may further deposit the accepted author's version on a funder's repository at a funder's request, provided it is not made publicly available until 12 months after publication.
Journal of Applied Microbiology, 2006
Aims: Azimsulfuron is a recently introduced sulfonylurea herbicide useful in controlling weeds in... more Aims: Azimsulfuron is a recently introduced sulfonylurea herbicide useful in controlling weeds in paddy fields. To date very little information is available on the biodegradation of this pesticide and on its effect on the soil microbial community. The aim of this work was to study its biodegradation both in slurry soil microcosms and in batch tests with mixed and pure cultures. Methods and Results: Azimsulfuron was applied to forest bulk soil in order to study its effect on the structure of the bacterial soil community, as detectable by denaturant gradient gel electrophoresis (DGGE) analyses. Biodegradation and abiotic processes were investigated by HPLC analyses. In addition, a microbial consortium was selected, that was able to use azimsulfuron as the sole energy and carbon source. One of the metabolites produced by the consortium was isolated and identified through LC-MS analyses. Cultivable bacteria of the consortium were isolated and identified by 16S rDNA sequencing (1400 bp). Conclusions: Azimsulfuron treatment seems to have the ability to cause changes in the bacterial community structure that are detectable by DGGE analyses. It is easily biodegraded both in microcosms and in batch tests, with the formation of an intermediate that was identified as 2-methyl-4-(2-methyl-2H-tetrazol-5-yl)-2H-pyrazole-3-sulfonamide. Significance and Impact of the Study: The study increases the knowledge on the biodegradation of azimsulfuron and its effects on the soil microbiota.
Environmental Microbiology
It has been previously shown that the transgenic overexpression of the plant root vacuolar proton... more It has been previously shown that the transgenic overexpression of the plant root vacuolar proton pumps H +-ATPase (V-ATPase) and H +-PPase (V-PPase) confer tolerance to drought. Since plant-root endophytic bacteria can also promote drought tolerance, we hypothesize that such promotion can be associated to the enhancement of the host vacuolar proton pumps expression and activity. To test this hypothesis, we selected two endophytic bacteria endowed with an array of in vitro plant growth promoting traits. Their genome sequences confirmed the presence of traits previously shown to confer drought resistance to plants, such as the synthesis of nitric oxide and of organic volatile organic compounds. We used the two strains on pepper (Capsicuum annuum L.) because of its high sensitivity to drought. Under drought conditions, both strains stimulated a larger root system and enhanced the leaves' photosynthetic activity. By testing the expression and activity of the vacuolar proton pumps, H +-ATPase (V-ATPase) and H +-PPase (V-PPase), we found that bacterial colonization enhanced V-PPase only. We conclude that the enhanced expression and activity of V-PPase can be favoured by the colonization of drought-tolerance-inducing bacterial endophytes.
Microbial Ecology, 2011
The Grande Albergo Ausonia & Hungaria (Venice Lido, Italy) has an Art Nouveau polychrome ceramic ... more The Grande Albergo Ausonia & Hungaria (Venice Lido, Italy) has an Art Nouveau polychrome ceramic coating on its façade, which was restored in 2007. Soon after the conservation treatment, many tiles of the façade decoration showed coloured alterations putatively attributed to the presence of microbial communities. To confirm the presence of the biological deposit and the stratigraphy of the Hungaria tiles, stereomicroscope, optical and environmental scanning electron microscope observations were made. The characterisation of the microbial community was performed using a PCR-DGGE approach. This study reported the first use of a culture-independent approach to identify the total community present in biodeteriorated artistic tiles. The case study examined here reveals that the coloured alterations on the tiles were mainly due to the presence of cryptoendolithic cyanobacteria. In addition, we proved that the microflora present on the tiles was generally greatly influenced by the environment of the Hungaria hotel. We found several microorganisms related to the alkaline environment, which is in the range of the tile pH, and related to the aquatic environment, the presence of the acrylic resin Paraloid B72® used during the 2007 treatment and the pollutants of the Venice lagoon.
International Biodeterioration & Biodegradation, 2011
The external walls of the Cathedral of Florence are made of green serpentine, red marlstone and C... more The external walls of the Cathedral of Florence are made of green serpentine, red marlstone and Carrara white marble, and intensive air pollution attack has led to their weathering, which caused black crust formation. A study was performed to evaluate the most appropriate cleaning treatment for black crust removal, adopting chemical (ammonium carbonate poultice), laser (1064 nm, Nd:YAG laser), and microbial (poultice embedding sulfate-reducing bacteria) cleaning. The effects of the different procedures on the original surfaces were evaluated by scanning electron microscopy coupled with energy dispersive X-ray (SEM/EDS) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, and color measurements. One year later further color measurements were made. It was found that chemical cleaning led to non-homogeneous crust removal and that for the extremely powdery and incoherent red substratum the preferred treatment was laser cleaning. Overall, the most satisfactory treatment was the microbial cleaning process. It was the most controllable process and the most efficient for sulfate removal. Its main drawback appears to be the time needed to remove thick black crusts since numerous applications were necessary.
Water science and technology : a journal of the International Association on Water Pollution Research, 2002
In order to improve activated sludge plant operation (achieving higher efficiency and cost saving... more In order to improve activated sludge plant operation (achieving higher efficiency and cost savings) beside influent and effluent characteristics and working parameters (e.g. dissolved oxygen, total and volatile suspended solids, pH, recirculation flow rate, etc.), the biomass activity should be monitored, the bacteria being responsible for the pollutant degradation. Since conventional cultivation based methods are inadequate to quantify environmental microorganisms (due to scarce number of cultivable microorganisms and time-consuming procedures) several "non-conventional" techniques were applied in this study, in order to compare the obtainable information and their routine feasibility. Different measurements (VSS concentration, Oxygen Uptake Rate, microbial counts by cultural and biomolecular methods--MPN-PCR, ATP content, dehydrogenase activity, microbial cell viability and enzymatic activity) were carried out on mixed liquor samples, taken from a municipal activated slu...
Annali Di Storia Delle Universita Italiane 11, 2007
Current Microbiology, 1983
We have investigated the number of methanogenic bacteria in different samples of fresh feces and ... more We have investigated the number of methanogenic bacteria in different samples of fresh feces and effluents from the anaerobic digestion of cattle and swine waste and municipal sludges. We have further compared conventional anaerobic techniques with the rigorous, oxygen-free, anaerobic, experimental conditions obtained in a controlled glove cabinet atmosphere. It was found that the total number of oxygen-intolerant methanogenic bacteria
Of Microbes and Art, 2000
Journal of Environmental Science and Health . Part A: Environmental Science and Engineering and Toxicology, 1995
... (ΙΟ5 cfu/ml) (15.), by Rossen et al. (2X105 cfu/ml) (8), and Wernars et al. Page 7. ... Inhib... more ... (ΙΟ5 cfu/ml) (15.), by Rossen et al. (2X105 cfu/ml) (8), and Wernars et al. Page 7. ... Inhibition of PCR by various components of some food has been described also by Rossen et al (16). A method for avoiding inhibition has been proposed by Fluit et al.(14). ...
PROTEOMICS, 2005
During 1391-1392, Spinello Aretino painted a cycle of frescoes in Pisa's cemetery on the theme "S... more During 1391-1392, Spinello Aretino painted a cycle of frescoes in Pisa's cemetery on the theme "Storie dei Santi Martiri Efisio e Potito", highly prized by contemporaries and by Vasari. Twenty years ago, one of these frescoes, "Conversione di S. Efisio e Battaglia" (Conversion of S. Efisio and Battle), because of discolouring and bad damage caused by humidity and atmospheric pollution, was removed from the walls using the "tear-off" technique, consisting in covering the surface with a strong cloth bound to the surface with generous layers of formaldehyde-treated glue. As luck would have it, this large fresco (3.50 6 7.80 m) was abandoned in a storehouse for more than 20 years. When the curators attempted to remove the cloth, much to their dismay they found that the glue resisted any attempt at digestion, even when treated with concoctions of the most aggressive proteolytic enzymes available on the market. It is likely that during the long storage the glue became slowly cross-linked by the formaldehyde to the point of forming an intricate mass of untreatable proteinaceous material. Thus, although poor Spinello died presumably as a bona fide Christian, his painting was condemned to wear the burka, Muslim-fashion, for the rest of its life. When we recently treated the fresco with a suspension of viable Pseudomonas stutzeri cells, these bacteria, although agnostic, were able to fully digest the hardened glue and restore to life Spinello's glorious painting. We show here how proteomics helped us solve the riddle of how these bacteria acted on the burka-obscured fresco.
Microbiology of Composting, 2002
Http Dx Doi Org 10 1081 Pfc 120025557, Feb 6, 2007
Two sulfonylurea herbicides, chlorsulfuron and metsulfuron-methyl, were studied under laboratory ... more Two sulfonylurea herbicides, chlorsulfuron and metsulfuron-methyl, were studied under laboratory conditions, in order to elucidate the biodegradation pathway operated by Aspergillus niger, a common soil fungus, which is often involved in the degradation of xenobiotics. HPLC-UV was used to study the kinetic of degradation, whereas LC-MS was used to identify the metabolites structure. In order to avoid the chemical degradation induced by a decrease in pH, due to the production of citric acid by the fungus, the experiments were performed in a buffered neutral medium. No significant degradation for both compounds was observed in mineral medium with 0.2% sodium acetate. On the contrary, in a rich medium, after 28 days the degradations, chemical degradation excluded, were about 30% for chlorsulfuron and 33% for metsulfuron-methyl. The main microbial metabolites were obtained via cleavage of the sulfonylurea bridge. In addition the fungus seems to be able to hydroxylate the aromatic ring of chlorsulfuron. In the case of metsulfuron-methyl the only detected metabolite was the triazine derivative, while the aromatic portion was completely degraded. Finally, the demethylation of the methoxy group on the triazine ring, previously observed with a Pseudomonas fluorescens strain, was not observed with A. niger.
Applied and Environmental Microbiology, 2006
An improved methodology to remove black crusts from stone by using Desulfovibrio vulgaris subsp. ... more An improved methodology to remove black crusts from stone by using Desulfovibrio vulgaris subsp. vulgaris ATCC 29579, a sulfate-reducing bacterium, is presented. The strain removed 98% of the sulfates of the crust in a 45-h treatment. Precipitation of black iron sulfide was avoided using filtration of a medium devoid of iron. Among three cell carriers, Carbogel proved to be superior to both sepiolite and Hydrobiogel-97, as it allowed an easy application of the bacteria, kept the system in a state where microbial activity was maintained, and allowed easy removal of the cells after the treatment.
Microbial Ecology, 2009
A rosy discoloration partly masking the Luca Signorelli frescoes in St. Brizio Chapel (Orvieto Ca... more A rosy discoloration partly masking the Luca Signorelli frescoes in St. Brizio Chapel (Orvieto Cathedral, Italy) for many years proved to be a biological alteration, so the present research focused on investigating biodeteriogens and selecting an appropriate biocide to treat them. Optical epifluorescence and electronic microscopic observations of the rosy powder revealed a prevalent autofluorescent coccoid form with a diameter bigger than 5 μm. Chlorophylls a and b were extracted, suggesting the presence of cyanobacteria, a thesis subsequently confirmed by flow cytometry. Cultural media were inoculated with the rosy powder, and microorganisms grew as a green patina in phototrophic conditions and as a rosy patina when organic compounds were added to the mineral medium. The rosy discoloration was most likely caused by the presence of phycoerythrin. The sequencing of the cyanobacteriaspecific polymerase chain reaction (PCR)-DGGE bands matched, with a similarity percentage >94, uncultured cyanobacteria, and the sequences were deposited in the GenBank under EU874241, EU874242, EU874243, EU874244, EU874245, EU874246, and EU874247. Finally, the efficiency of the two biocides Neo Desogen and Metatin 5810-101, both based on benzalkonium chloride, was evaluated using adenosine triphosphate measurements and PCR-based detection of cyanobacteria. Metatin, used in situ at 2% of the trade product, proved to be the better biocide, no cyanobacteria being detected after the Metatin treatment.
Critical Reviews in Food Science and Nutrition, Nov 7, 2011
The fate of dietary DNA in the gastrointestinal tract (GIT) of animals has gained renewed interes... more The fate of dietary DNA in the gastrointestinal tract (GIT) of animals has gained renewed interest after the commercial introduction of genetically modified organisms (GMO). Among the concerns regarding GM food, are the possible consequences of horizontal gene transfer (HGT) of recombinant dietary DNA to bacteria or animal cells. The exposure of the GIT to dietary DNA is related to the extent of food processing, food composition, and to the level of intake. Animal feeding studies have demonstrated that a minor amount of fragmented dietary DNA may resist the digestive process. Mammals have been shown to take up dietary DNA from the GIT, but stable integration and expression of internalized DNA has not been demonstrated. Despite the ability of several bacterial species to acquire external DNA by natural transformation, in vivo transfer of dietary DNA to bacteria in the intestine has not been detected in the few experimental studies conducted so far. However, major methodological limitations and knowledge gaps of the mechanistic aspects of HGT calls for methodological improvements and further studies to understand the fate of various types of dietary DNA in the GIT.
Fems Microbiol Lett, 1998
Applied and Environmental Microbiology, Mar 1, 1999
Aiming to develop a DNA marker specific for Bacillus anthracis and able to discriminate this spec... more Aiming to develop a DNA marker specific for Bacillus anthracis and able to discriminate this species from Bacillus cereus, Bacillus thuringiensis, and Bacillus mycoides, we applied the randomly amplified polymorphic DNA (RAPD) fingerprinting technique to a collection of 101 strains of the genus Bacillus, including 61 strains of the B. cereus group. An 838-bp RAPD marker open reading frame highly homologous to the ypuA gene of Bacillus subtilis. The restriction analysis of the SG-850 fragment with AluI distinguished B. anthracis from the other species of the B. cereus group.
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Papers by Claudia Sorlini