The genome sequence of Streptomyces lividans 66 reveals a novel tRNA-dependent peptide biosynthetic system within a metal-related genomic island

Microbial Biotechnolog

Identification and Phylogenetic Analysis of Tityus pachyurus and Tityus obscurus Novel Putative Na+-Channel Scorpion Toxins

Background: Colombia and Brazil are affected by severe cases of scorpionism. In Colombia the most dangerous accidents are caused by Tityus pachyurus that is widely distributed around this country. In the Brazilian Amazonian region scorpion stings are a common event caused by Tityus obscurus. The main objective of this work was to perform the molecular cloning of the putative Na+-channel scorpion toxins (NaScTxs) from T. pachyurus and T. obscurus venom glands and to analyze their phylogenetic relationship with other known NaScTxs from Tityus species. Methodology/Principal Findings: cDNA libraries from venom glands of these two species were constructed and five nucleotide sequences from T. pachyurus were identified as putative modulators of Na+-channels, and were named Tpa4, Tpa5, Tpa6, Tpa7 and Tpa8; the latter being the first anti-insect excitatory b-class NaScTx in Tityus scorpion venom to be described. Fifteen sequences from T. obscurus were identified as putative NaScTxs, among which three had been previously described, and the others were named To4 to To15. The peptides Tpa4, Tpa5, Tpa6, To6, To7, To9, To10 and To14 are closely related to the a-class NaScTxs, whereas Tpa7, Tpa8, To4, To8, To12 and To15 sequences are more related to the b-class NaScTxs. To5 is possibly an arthropod specific toxin. To11 and To13 share sequence similarities with both a and b NaScTxs. By means of phylogenetic analysis using the Maximum Parsimony method and the known NaScTxs from Tityus species, these toxins were clustered into 14 distinct groups. Conclusions/Significance: This communication describes new putative NaScTxs from T. pachyurus and T. obscurus and their phylogenetic analysis. The results indicate clear geographic separation between scorpions of Tityus genus inhabiting the Amazonian and Mountain Andes regions and those distributed over the Southern of the Amazonian rainforest. Based on the consensus sequences for the different clusters, a new nomenclature for the NaScTxs is proposed

Mammalian cell entry genes in Streptomyces may provide clues to the evolution of bacterial virulence

Understanding the evolution of virulence is key to appreciating the role specific loci play in pathogenicity. Streptomyces species are generally non-pathogenic soil saprophytes, yet within their genome we can find homologues of virulence loci. One example of this is the mammalian cell entry (mce) locus, which has been characterised in Mycobacterium tuberculosis. To investigate the role in Streptomyces we deleted the mce locus and studied its impact on cell survival, morphology and interaction with other soil organisms. Disruption of the mce cluster resulted in virulence towards amoebae (Acanthamoeba polyphaga) and reduced colonization of plant (Arabidopsis) models, indicating these genes may play an important role in Streptomyces survival in the environment. Our data suggest that loss of mce in Streptomyces spp. may have profound effects on survival in a competitive soil environment, and provides insight in to the evolution and selection of these genes as virulence factors in related pathogenic organisms

7th Drug hypersensitivity meeting: part two

No abstract availabl

Minimum Information about a Biosynthetic Gene cluster

A wide variety of enzymatic pathways that produce specialized metabolites in bacteria, fungi and plants are known to be encoded in biosynthetic gene clusters. Information about these clusters, pathways and metabolites is currently dispersed throughout the literature, making it difficult to exploit. To facilitate consistent and systematic deposition and retrieval of data on biosynthetic gene clusters, we propose the Minimum Information about a Biosynthetic Gene cluster (MIBiG) data standard.Chemistry and Chemical Biolog

Picaduras por escorpión Tityus asthenes en Mutatá, Colombia: aspectos epidemiológicos, clínicos y toxinológicos

Introduction. Scorpion stings are a public health problem in many countries. However, in Colombia, very few epidemiological, clinical or toxicological studies have been undertaken.Objective. Ecological and epidemiological aspects were related to the prevalence of scorpion stings by Tityus asthenes. The clinical features of envenomization were described in patients and in an experimental animal model.Materials and methods. The study was conducted in four localities of Mutatá and Urabá Counties in the province of Antioquia, Colombia. The sample consisted of 1,593 (929 urban, 664 rural) of the 5,305 exposed people, inhabitating 324 households (188 urban (58%); 136 rural (42%) of 1,448 houses total in the study area. An interview survey was performed in every selected family for a more realistic estimate of sting prevalence. Additionally, a prospective study was directed toward patients presenting scorpion stings at care at the local hospital over an 18-month period.Results. The probability was 12.9 times greater of finding T. asthenes inside or around houses in places near to forest and high agrarian plantations (odds ratio=13). Eighty scorpion stings were reported in the retrospective study (4.1% prevalence [95% CI 3.3-4.8%] ), but only 14 of the patients (17.5%) sought care in the local hospital (an 82.5% underreportage). Seventy percent of the stings occurred in rural places; 50% occurred in the locality of Caucheras, with an attack rate of 10.6%. The overall household infestation rate was 269% (95% CI 22.9-30.8%) and an area dispersion ratio of 100%. Signs of systemic envenomization occurred mainly in children (67%). The 50% lethal dose of T. asthenes venom was 121.6 μg for 18-20 g Swiss Webster rats (95% CI 103.7-139.6). Immunodetection of T. asthenes and Centruroides gracilis/C.margantatus venoms in the experimental animals was possible when were tested by Western blot against Alacramyn® (Instituto Bioclón, México) and Soro antiaracnídico® (Instituto Butantan, Brasil) antivenoms. Scorpion interspecific differences were noted.Conclusions. The prevalence of stings by T. asthenes were common and their presence was associated with tropical rainforests. Envenomization at low density can be neutralized efficiently by anti-scorpion antivenoms produced in México and Brazil but with differing specificities for the venom of each scorpion species.Introducción. El escorpionismo afecta a países tropicales como Colombia.Objetivo. Determinar los indicadores ecológicos y epidemiológicos de las picaduras por Tityus asthenes en cuatro localidades de Mutatá, Colombia, y las características clínicas del envenenamiento y toxinológicas del veneno.Materiales y métodos. Es un estudio prospectivo/retrospectivo descriptivo y experimental; se visitaron aleatoriamente 324 de las 1.448 viviendas del municipio: 188 urbanas (58,0%) y 136 rurales (42,0%), con 1.593 habitantes. En 18 meses se estudiaron prospectivamente los pacientes picados por T. asthenes que ingresaron al hospital local y, retrospectivamente en encuestas domiciliarias, se determinó el subregistro. Se recolectaron escorpiones vivos y se realizaron experimentos con el veneno.Resultados. Hubo 12,9 más probabilidades de hallar ejemplares de T. asthenes en el área rural (OR=6,5; IC95% 3,9-10,8), en el intradomicilio y peridomicilio cercano a bosques y plantaciones agrarias altas (OR=13,0; IC95% 7,5-23,0). Se reportaron 80 picaduras ocurridas en los dos últimos años (prevalencia de 4,1%; IC95% 4,8-3,3); sólo 14 personas (17,5%) consultaron al hospital (subregistro de 82,5%). La prevalencia ponderada de infestación por escorpiones en las viviendas encuestadas fue de 26,9% (112 casas) (IC95% 30,8-22,9). El 50% de los accidentes ocurrió en la localidad de Caucheras: 10,6% de proporción de ataque. El envenenamiento sistémico fue más frecuente en niños (67%). La dosis letal 50 del veneno en ratones de 18 a 20 g, fue 121,6 μg (IC95% 103,7-139,6). Hubo reactividad inmunológica por Western blot de los antivenenos del Instituto Bioclón, México (Alacramyn®) y del Instituto Butantan, Brasil (Soro antiaracnídico®) con los venenos de T. asthenes y Centruroides gracilis/Centruroides margaritatus de Colombia.Conclusiones. Las picaduras por T. asthenes, con elevado subregistro, están asociadas a viviendas cercanas a bosques húmedos tropicales. Su veneno y el de C. gracilis, con diferencias de especificidad, reaccionaron con los antivenenos producidos en México y Brasil

Archivos de zootecnia. Editorial report 2015

The editorial process of Archivos de Zootecnia during 2015 is reported below. A total of 345 manuscripts coming from 24 countries, mainly from Brazil (almost 70 %), were received. Consequently, the most frequently used language in the manuscripts was Portuguese, followed by Spanish and English. 71 works were published in 2015: 54 articles, 13 short notes and 4 reviews. Published writings came from 15 countries. The two main topics the articles were about were Feeding and food (n= 36, 40 %) and Breeding and genetics (n= 19, 21.1 %); while the most frequent species the works dealt with was cattle (n= 24, 26.67 %). Editorial times between the reception and publication of the manuscripts have comparatively improved according to the results showed in previous years’ reports.El proceso editorial de Archivos de Zootecnia durante el 2015 se muestra a continuación. Se recibieron un total de 345 manuscritos procedentes de 24 países, siendo Brasil el país que ha contribuido en mayor medida (casi el 70%). Consecuentemente, el lenguaje más usado en los trabajos fue el portugués, seguido del español y el inglés. En 2015 se editaron un total de 71 publicaciones: 54 artículos, 13 notas breves y 4 revisiones. Los trabajos procedían de 15 países. Los principales temas objeto de publicación fueron Alimentación y Alimentos (n= 36, 40 %) y Razas y Genética (n= 19, 21,1 %); mientras que la principal especie sobre la que se publicó fue la especie bovina (n= 24, 26,67 %). Los tiempos editoriales entre la recepción y publicación de los trabajos han mejorado con respecto a los últimos años de acuerdo a los resultados mostrados en informes editoriales previos