Renibacterium salmoninarum is the causative agent of bacterial kidney disease (BKD), which is a commercially important disease of farmed salmonids. Typing by conventional methods provides limited information on the evolution and spread of this pathogen, as there is a low level of standing variation within the R. salmoninarum population. Here, we apply whole-genome sequencing to 42 R. salmoninarum isolates from Chile, primarily from salmon farms, in order to understand the epidemiology of BKD in this country. The patterns of genomic variation are consistent with multiple introductions to Chile, followed by rapid dissemination over a 30 year period. The estimated dates of introduction broadly coincide with major events in the development of the Chilean aquaculture industry. We find evidence for significant barriers to transmission of BKD in the Chilean salmon production chain that may also be explained by previously undescribed signals of host tropism in R. salmoninarum. Understanding the genomic epidemiology of BKD can inform disease intervention and improve sustainability of the economically important salmon industry. This article contains data hosted by Microreact.

Fourteen species of fungus were isolated from the lower digestive tract of 39 of 80 pigeons. Sixteen pigeons had concurrent isolations while two harbored three species. Fungi isolated were Allescheria boydii, Aspergillus spp., Candida krusei, Chrysosporium spp., Geotrichum candidum, Mucor spp., Paeciliomyces spp., Penicillium spp., Rhizopus spp., Rhodotorula spp., Scopulariopsis spp., Streptomyces spp., and Trichosporon cutaneum. There was no apparent evidence that these fungi were associated with clinical disease in any of the pigeons.

No abstract

Historical monuments and buildings represent an important part of the cultural legacy of past civilizations, in addition to being considered sites of endemic diversity, knowledge of this is essential, especially in photosynthetic organisms, since they are the pioneers in the establishment of those communities. Even though the morphological identification of photosynthetic microorganisms represents a challenge due to the phenotypic plasticity they present, so the use of Molecular Biology techniques is essential. The objective of this work was to identify species of microalgae and cyanobacteria present in three archaeological zones: Malinalco and Teotihuacán of the State of Mexico and Yohualichan, of the State of Puebla, through the partial amplification of the genes that code for the 16S rRNA and 18S rRNA subunits by the PCR technique using 2 pairs of primers and the sequencing of the amplified ones. In this way, 3 of the 10 strains isolated at the species level were identified: Chlorella sorokiniana, Chlorococcum vacuolatum and Klebsormidium crenulatum, and the other just at genus level because some initiators did not provide enough information. In this way, the use of morphological and molecular characters contributes to a more complete and reliable taxonomic identification.

No abstract