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Introduction: The light-emitting enzyme complex of luminescent bacteria is a powerful biochemical tool, with a wide variety of applications including environmental quality monitoring. Objectives: To identify taxonomically two luminescent bacteria from Cuban shelf waters, as well as select the culture media that favor their growth and luminescence. Methods: The taxonomic location of the luminescent bacteria was carried out using traditional and molecular methods. Four culture media (LM, Boss, Chalk, ZoBell) were evaluated as a function of specific growth rate (µ) and luminescence, using a Genesys 10UV spectrophotometer and a Shimadzu RF-5301pc spectrofluorometer, respectively. Results: Biochemical and physiological characterization of CBM-976 and CBM-992 isolates showed similarities with Vibrio harveyi species. Phylogenetic positioning analysis confirmed a high correspondence with V. harveyi strains isolated from aquatic environments, using partial sequences of 16S rRNA, gyrB and pyrH genes. LM and ZoBell culture media were selected for having a high specific growth rate of CBM-976 and CBM-992 strains, as well as for showing high luminescence values. The results will allow deepening the physiological characterization and are the starting point for the development of contaminant detection methods. Conclusions: The rational combination of physiological and biochemical characteristics, as well as the molecular approach, contributed to determine the taxonomic position of CBM-976 and CBM-992 strains isolated from Cuban marine waters as Vibrio harveyi. Furthermore, LM and ZoBell culture media were selected as the most suitable for growth and luminescence emission for both strains. [ABSTRACT FROM AUTHOR]

Objective. To report the infection with Leptospira in the kidneys of bats from Campeche and Yucatán, Mexico, through the amplification by PCR of two different 16S RNA ribosomal gene fragments. Materials and methods. Bat captures were carried out at one site in Campeche and two sites in Yucatán. Euthanasia was applied to the captured bats and a necropsy was performed to collect a renal tissue sample that was used in the total DNA extraction. Two different conventional PCR were performed for the amplification of the 16S RNA ribosomal gene fragments. Some sequences from positive products were obtained and analyzed with bioinformatics tools to identify the infectious species of Leptospira. Results. Sixty-nine bats belonging to four families and eight different species were captured. The family with the greatest diversity was Phyllostomidae with five species. The most captured species was Artibeus jamaicensis (41, 59.4%). Both PCR showed a global infection frequency of 21.7%. The infected species were A. jamaicensis, Pteronotus parnellii, and Chiroderma villosum. The bioinformatic analysis of the positive products yielded a 99.0% identity for Leptospira noguchii, Leptospira borgpetersenii, and Leptospira santarosai. Conclusions. Some bat species of Yucatán and Campeche, Mexico, are renal carriers of pathogenic Leptospira, therefore participating in the transmission cycle in the region. The frequency of infection found in the renal tissue of the captured bats is higher than the one obtained from other reservoirs captured in Yucatán and Campeche. New species of bats are reported as renal Leptospira carriers in Mexico. [ABSTRACT FROM AUTHOR]

Our work reports the use of genomic DNA primers previously purified from reference strains to detect and identify the microorganisms that cause bacterial meningocephalitis (BME) in 24 samples of cerebrospinal fluid (CSF). General and specific primers derived from the 16S rRNA (ribosomal RNA) gene were used. The general primers were amplified in all the bacterial species analyzed: Neisseria meningitidis, type b Haemophylus influenzae and Streptococcus sp. in the same 825 pb band, but the specific ones only amplified in the microorganism from which they were derived. Bands of 667, 478 and 253 pb were respectively obtained for N. meningitidis, H. influenzae and Streptococcus sp. Streptococcus agalactiae was also detected by PCR in which a 478 pb band was obtained. Upon evaluating the primers in clinical CSF samples, 100% detection of the BME causing microorganisms was observed. The specificity was 100%. The PCR products were analyzed by Hae III digestion, and correspondence found for the restriction patterns of the clinical samples and the reference strains. [ABSTRACT FROM AUTHOR]