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Militello in Val di Catania, Italy

Giannone V.,Science and Technology Park of Sicily | Longo C.,Science and Technology Park of Sicily | Damigella A.,Science and Technology Park of Sicily | Raspagliesi D.,University of Catania | And 2 more authors.
Journal of Industrial Microbiology and Biotechnology | Year: 2010

Properties of 13 Saccharomyces cerevisiae strains isolated from different sources (traditional sourdoughs, industrial baking yeasts etc.) were studied in dough produced with durum wheat (Sicilian semolina, variety Mongibello). Durum wheat semolina and durum wheat flour are products prepared from grain of durum wheat (Triticum durum Desf.) by grinding or milling processes in which the bran and germ are essentially removed and the remainder is comminuted to a suitable degree of fineness. Acidification and leavening properties of the dough were evaluated. Strains isolated from traditional sourdoughs (DSM PST18864, DSM PST18865 and DSM PST18866) showed higher leavening power, valuable after the first and second hours of fermentation, than commercial baking yeasts. In particular the strain DSM PST 18865 has also been successfully tested in bakery companies for the improvement of production processes. Baking and staling tests were carried out on five yeast strains to evaluate their fermentation ability directly and their resistance to the staling process. Amplified fragment length polymorphism (fAFLP) was used to investigate genetic variations in the yeast strains. This study showed an appreciable biodiversity in the microbial populations of both wild and commercial yeast strains. © 2009 Society for Industrial Microbiology. Source

Trantas E.A.,Technological Educational Institute of Crete | Licciardello G.,Science and Technology Park of Sicily | Almeida N.F.,Federal University of Mato Grosso do Sul | Witek K.,John Innes Center | And 11 more authors.
Frontiers in Microbiology | Year: 2015

The non-fluorescent pseudomonads, Pseudomonas corrugata (Pcor) and P. mediterranea (Pmed), are closely related species that cause pith necrosis, a disease of tomato that causes severe crop losses. However, they also show strong antagonistic effects against economically important pathogens, demonstrating their potential for utilization as biological control agents. In addition, their metabolic versatility makes them attractive for the production of commercial biomolecules and bioremediation. An extensive comparative genomics study is required to dissect the mechanisms that Pcor and Pmed employ to cause disease, prevent disease caused by other pathogens, and to mine their genomes for genes that encode proteins involved in commercially important chemical pathways. Here, we present the draft genomes of nine Pcor and Pmed strains from different geographical locations. This analysis covered significant genetic heterogeneity and allowed in-depth genomic comparison. All examined strains were able to trigger symptoms in tomato plants but not all induced a hypersensitive-like response in Nicotiana benthamiana. Genome-mining revealed the absence of type III secretion system and known type III effector-encoding genes from all examined Pcor and Pmed strains. The lack of a type III secretion system appears to be unique among the plant pathogenic pseudomonads. Several gene clusters coding for type VI secretion system were detected in all genomes. Genome-mining also revealed the presence of gene clusters for biosynthesis of siderophores, polyketides, non-ribosomal peptides, and hydrogen cyanide. A highly conserved quorum sensing system was detected in all strains, although species specific differences were observed. Our study provides the basis for in-depth investigations regarding the molecular mechanisms underlying virulence strategies in the battle between plants and microbes. © 2015 Trantas, Licciardello, Almeida, Witek, Strano, Duxbury, Ververidis, Goumas, Jones, Guttman, Catara and Sarris. Source

Ialacci G.M.,University of Catania | Bella P.,University of Catania | Licciardello G.,Science and Technology Park of Sicily | Strano C.P.,University of Catania | And 4 more authors.
Plant Pathology | Year: 2016

Clavibacter michiganensis subsp. michiganensis (Cmm) strains, collected in greenhouses from 17 farms during tomato bacterial canker outbreaks occurring between 2005 and 2008 in Sicily, were analysed by a multiphasic approach. Population studies were conducted to investigate the possible sources of inocula. Cmm strains were characterized by PCR assays targeting virulence genes, fingerprinting techniques, metabolic profiles and virulence. These strains were comparatively analysed with Cmm strains isolated in other parts of Italy over a period of 15 years. Chromosomal genes encoding virulence determinants tomA, ppaA, chpC, and the plasmid-encoded genes pat-1 and celA were detected by PCR in all tested strains, except for four Sicilian Cmm strains where the pat-1 gene was not amplified. Using BOX-PCR, Cmm strains were differentiated into 13 haplotypes and clonal populations were identified. Cmm strains isolated from different farms in 2008 showed the same BOX-PCR haplotype. A distinct BOX-PCR haplotype was obtained from atypical Cmm strains lacking pat-1 and isolated in 2006/7 from three farms. Cmm strains with two different haplotypes were detected in one farm, whereas the other farms contained strains with only a single haplotype. A new fAFLP protocol based on the amplification of ApaI/MseI fragments was developed and was able to differentiate C. michiganensis subspecies. Different populations were delineated for the multiple outbreaks occurring in Sicily, whereas similar populations were recorded in other Italian regions over a period of 12 years. The results are consistent with previous studies that demonstrate that Cmm outbreaks are associated with propagation material. © 2016 British Society for Plant Pathology. Source

Licciardello G.,Science and Technology Park of Sicily | Strano C.P.,University of Catania | Bertani I.,Bacteriology Group | Bella P.,University of Catania | And 4 more authors.
Journal of Biotechnology | Year: 2012

Pseudomonas corrugata and Pseudomonas mediterranea are two closely related phytopathogenic bacteria both causal agents of tomato pith necrosis. P. corrugata produces phytotoxic and antimicrobial cationic lipodepsipeptides (LDPs) which are thought to act as major virulence factors. Previous studies have demonstrated that P. corrugata CFBP 5454 has an N-acyl homoserine lactone (AHL) quorum sensing (QS) system PcoI/PcoR and that LDP production occurs at high population densities. No molecular studies on virulence have thus far been reported for P. mediterranea. In this study, we show that P. mediterranea also produces LDPs as well as possessing an AHL-dependent QS system, designated PmeI/PmeR, which is highly homologous to the PcoI/R system of P. corrugata producing and responding to C6-AHL. Downstream of pmeI, a partial DNA sequence revealed the presence of a homolog of the rfiA gene of P. corrugata which encodes a transcriptional regulator involved in bacterial virulence. Pathogenicity tests and MALDI-TOF spectra of wild-type strains of both bacterial species and their respective QSs and rfiA derivative mutants revealed that, in the absence of LDPs, the strains induce very weak symptoms indicating that LDPs may act as major virulence factors. Mutational analysis of both QS systems suggests that their mode of action is in places different. © 2011 Elsevier B.V. Source

Rizza S.,University of Catania | Conesa A.,Research Center Principe Felipe | Juarez J.,Instituto Valenciano Of Investigaciones Agrarias Ivia | Catara A.,Science and Technology Park of Sicily | And 3 more authors.
Molecular Plant Pathology | Year: 2012

Viroids are small (246-401 nucleotides), single-stranded, circular RNA molecules that infect several crop plants and can cause diseases of economic importance. Citrus are the hosts in which the largest number of viroids have been identified. Citrus exocortis viroid (CEVd), the causal agent of citrus exocortis disease, induces considerable losses in citrus crops. Changes in the gene expression profile during the early (pre-symptomatic) and late (post-symptomatic) stages of Etrog citron infected with CEVd were investigated using a citrus cDNA microarray. MaSigPro analysis was performed and, on the basis of gene expression profiles as a function of the time after infection, the differentially expressed genes were classified into five clusters. FatiScan analysis revealed significant enrichment of functional categories for each cluster, indicating that viroid infection triggers important changes in chloroplast, cell wall, peroxidase and symporter activities. © 2012 THE AUTHORS. MOLECULAR PLANT PATHOLOGY © 2012 BSPP AND BLACKWELL PUBLISHING LTD. Source

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