RESUMEN
Abstract Dietzia sp. 111N12-1, isolated from the seawater of South China Sea, shows strong petroleum hydrocarbons degradation activity. Here, we report the draft sequence of approximately 3.7-Mbp genome of this strain. To the best of our knowledge, this is the first genome sequence of Dietzia strain isolated from the sea. The genome sequence may provide fundamental molecular information on elucidating the metabolic pathway of hydrocarbons degradation in this strain.
Asunto(s)
Agua de Mar/microbiología , Actinomycetales/aislamiento & purificación , Actinomycetales/genética , Genoma Bacteriano , Hidrocarburos/metabolismo , Filogenia , Biodegradación Ambiental , Actinomycetales/clasificación , Actinomycetales/metabolismo , Petróleo/metabolismo , Secuencia de Bases , ChinaRESUMEN
The petroleum-derived degrading Dietzia cinnamea strain P4 recently had its genome sequenced and annotated. This allowed employing the data on genes that are involved in the degradation of n-alkanes. To examine the physiological behavior of strain P4 in the presence of n-alkanes, the strain was grown under varying conditions of pH and temperature. D. cinnamea P4 was able to grow at pH 7.0-9.0 and at temperatures ranging from 35 ºC to 45 ºC. Experiments of gene expression by real-time quantitative RT-PCR throughout the complete growth cycle clearly indicated the induction of the regulatory gene alkU (TetR family) during early growth. During the logarithmic phase, a large increase in transcriptional levels of a lipid transporter gene was noted. Also, the expression of a gene that encodes the protein fused rubredoxin-alkane monooxygenase was enhanced. Both genes are probably under the influence of the AlkU regulator.
Asunto(s)
Actinomycetales/genética , Actinomycetales/metabolismo , Alcanos/metabolismo , Perfilación de la Expresión Génica , Genes Bacterianos , Hidrocarburos/metabolismo , Redes y Vías Metabólicas/genética , Actinomycetales/crecimiento & desarrollo , Biotransformación , Concentración de Iones de Hidrógeno , Reacción en Cadena en Tiempo Real de la Polimerasa , TemperaturaRESUMEN
Extracellular secondary metabolites from 350 fungi and 94 actinomycetes were screened for larvicidal activity against Culex quinquefasciatus, Anopheles stephensi and Aedes aegypti. Of them, 133 fungal metabolites and 35 from actinomycetes were active. Two from Streptomyces sp. and one from Paecilomyces sp. were highly active with LC50 value of 1-3 microliters/ml. The metabolites were more toxic to C. quinquefasciatus than to A. stephensi or Ae. aegypti larvae.
Asunto(s)
Actinomycetales/metabolismo , Animales , Toxinas Bacterianas , Culicidae , Hongos/metabolismo , Larva , Micotoxinas , Control Biológico de VectoresRESUMEN
Se presenta un caso de artritis de rodilla por Streptomyces somaliensis, raro agente causal de micetomas, que predomina en el continente africano. Es el segundo caso encontrado en la Argentina, con aislamiento e identificación microbiológica del agente causal y el único donde se demostró compromiso intra-articular