A wide variety of contagious and environmental bacteria can cause bovine mastitis worldwide. Antibiotic therapy is currently used for the treatment of the disease, although its intensive use leads to the emergence of resistant strains. Bacteriocins arise as potential antibacterial option for mastitis treatment. The aim of this work was to analyze bacteriocin associated genes as Streptococcus uberis ubericin A (ubaA), ubericin A immunity protein (ubaI), uberolysin A (ublA), Lantibiotic nisin-U (nsuA and nsuB) in 68 S uberis strains. Furthermore, the ability of the strains to inhibit important mastitis pathogens was assayed. Results showed that genes were present in combination and all the strains carried at least one gene. Seven bacteriocion associated gene patterns were identified. S. uberis strains were able to inhibit different mastitis pathogens and the greatest inhibition was observed in CNS strains. The results obtained provide new insights on antibacterial activity produced by S. uberis strains against different mastitis pathogens and could contribute to the development of strategies to treat intramammary infections.

Sugarcane orange rust caused by Puccinia kuehnii has recently become an important disease in sugarcane crops and its spread is causing great concern to growers. In this study, we analyzed spores from symptomatic orange rust sugarcane leaves collected in multiple locations in Cuba in a 4-year-period in order to characterize morphological traits of P. kuehnii, establish an adequate molecular technique to characterize it, and determine its infection court in sugarcane. Orange rust caused by P. kuehnii was confirmed by polymerase chain reaction (PCR) and morphological characterization. AFLP markers detected high diversity in P. kuenhnii samples. Sequencing of rDNA regions, as expected, did not reveal differences and SSR markers designed for P. melanocephala could not be transferred to P. kuehnii. In addition to stomata, entry through prickles was also detected as a new infection court in sugarcane. Although the presence of pustules on the adaxial leaf surface was frequently detected, no clear correlation between this presence and density of stomata and/or prickles was found.

No abstract

No abstract

No abstract