The role of prophage in plant-pathogenic bacteria

A diverse set of phage lineages is associated with the bacterial plant-pathogen genomes sequenced to date. Analysis of 37 genomes revealed 5,169 potential genes (approximately 4.3 Mbp) of phage origin, and at least 50 had no function assigned or are nonessential to phage biology. Some phytopathogens have transcriptionally active prophage genes under conditions that mimic plant infection, suggesting an association between plant disease and prophage transcriptional modulation. The role of prophages within genomes for cell biology varies. For pathogens such as Pectobacterium, Pseudomonas, Ralstonia, and Streptomyces, involvement of prophage in disease symptoms has been demonstrated. In Xylella and Xanthomonas, prophage activity is associated with genome rearrangements and strain differentiation. For other pathogens, prophage roles are yet to be established. This review integrates available information in a unique interface (http://propnav.esalq.usp.br) that may be assessed to improve research in prophage biology and its association with genome evolution and pathogenicity. © Copyright ©2013 by Annual Reviews. All rights reserved.

Evaluation of the psychrotrophic specific signatures for cspA gene and 16S rDNA on the phenotype of Bacillus cereus sensu strictu

This study characterised the psychrotrophic genotypes and phenotypes behaviour of 63 strains of Bacillus cereus sensu stricto isolated from dairy products. The presence of the cspA gene signature and the 16S rDNA mesophilic and/or psychrotrophic specific signatures was evaluated. Among the strains, 25 (39.7%) had the cspA gene signature, 38 (60.3%) had both mesophilic and psychrotrophic 16S rDNA signatures, 24 (38.1%) had only mesophilic and one exhibited only psychrotrophic. No strain grew at 7 °C. The results indicate that the presence of psychrotrophic signatures for cspA gene or the 16S rDNA did not ensure a psychrotrophic behaviour on a B. cereus phenotype. © 2013 Society of Dairy Technology.

Atividade proteolìtica de bactérias psicrotróficas em leites estocados em diferentes temperaturas

The widespread use of cooling technology as a tool for maintaining the microbiological and organoleptic characteristics of milk, Without effective hygienic practices throughout the milk production, caused the psychrotrophic micro-organisms to become major deteriorative bacteria in the dairy industry. The present study aimed to assess how the proteolytic psychrotrophic metabolism responds to different milk storage temperatures, drawing a parallel among psychrotrophic growth, amount of micro-organisms capable of breaking down proteins and amount of GMP (glycomacropeptide) released. Milk samples were collected directly from the cooling tank and subjected to count of psychrotrophs, count of proteolytic micro-organisms and the concentration of GMP at different storage times and temperatures. There was no linearity between the microbiological parameters and the GMP measured, according to the time/temperature binomial. The highest concentration of GMP (5.07 mg/mL) was measured in the binomial 8°C/24h (T8/ M24). The data make clear the need for further studies about questions involving the psychrotrophic microbiota in order to clarify extremely important basic questions about their metabolism.

Irradiação gama e armazenamento do mamão 'formosa' minimamente processado

Pós-graduação em Agronomia (Horticultura) - FCA

Características físico-químicas, sensoriais e higiênicas da carne bovina em duas classes de maturidade e sob influência da maturação

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Process for genetically engineering acidophilic bacteria and constructing a transformation vector

The present invention describes a method for transforming chemolithotrophic acidophilic bacteria using electroporation technology. The proposed method allows transforming a bacterial line using a transformation vector, the pAF vector, which contains an origin of vegetative replication that allows the vector to replicate inside the bacteria without altering the natural physiological functions of the latter. Also disclosed is the use of the bacteria modified according to the invention in bioleaching processes of sulphated copper, gold, uranium, nickel, zinc and cobalt ore, inter alia.

Plant growth promoting bacteria in Brachiaria brizantha

Brachiaria brizantha is considered one of the preferred fodders among farmers for having high forage yield and large production of root mass. The association of beneficial bacteria with these grasses can be very valuable in the recovery of the pasture areas with nutritional deficiency. With the aim of studying this possibility, we carried out the sampling of soil and roots of B. brizantha in three areas (Nova Odessa-SP, So Carlos-SP and Campo Verde-MT, Brazil). Seventy-two bacterial strains were isolated and used in tests to evaluate their biotechnological potential. Almost all isolates presented at least one positive feature. Sixty-eight isolates produced analogues of indole-3-acetic acid, ten showed nitrogenase activity when subjected to the method of increasing the concentration of total nitrogen (total N) in the culture medium and sixty-five isolates showed nitrogenase activity when subjected to acetylene reduction technique. The partial sequencing of 16S rRNA of these isolates allowed the identification of seven main groups, with the prevalence of those affiliated to the genus Stenotrophomonas (69 %). At the end, this work elected the strains C4 (Pseudomonadaceae) and C7 (Rhodospirillaceae) as promising organisms for the development of inoculants due to their higher nitrogenase activity.

A meta-analysis of the feed intake and growth performance of broiler chickens challenged by bacteria

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Phyllosphere Bacteria Improve Animal Contribution to Plant Nutrition

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Clinical Comparison of the Effectiveness of Single-file Reciprocating Systems and Rotary Systems for Removal of Endotoxins and Cultivable Bacteria from Primarily Infected Root Canals

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

One-Visit Versus Two-Visit Root Canal Treatment: Effectiveness in the Removal of Endotoxins and Cultivable Bacteria

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Rumen microbial diversity under influence of a polyclonal antibody preparation against lactate-producing and proteolytic bacteria in cows fed different energy sources

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Systematic Screening of Plant Extracts from the Brazilian Pantanal with Antimicrobial Activity against Bacteria with Cariogenic Relevance

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

A microbiota láctea: Importância na cadeia laticinista x deterioração

The work below boards critically the issues involved in the study of the microbiota of milk. It starts with a contextualization of the current dairy chain, in the presence of Normative Instruction - 51. Following are developed the most relevant concepts and definitions about the subject: the emergence of psychrotrophic, mesophilic acidifying metabolism, the injuries of marginal cooling. Next, the main genres that comprise the milky microbiota are described, in front of the following question: from what point the metabolism of these bacteria is no longer beneficial and becomes a deteriorating activity to the product? The paper does not end with classical conclusions or definite answers, but with questions, pointing out lines of research that can improve the quality of Brazilian milk, making it a differentiated and competitive product at the international market