Archive for the ‘Microbiology’ Category
A team of investigators of the flu has verified that the stumps of the influenza emigrate among different regions of the world, evolving along the way. This contradicts the common belief that the strains of influenza in the tropics are the source of seasonal epidemics worldwide.
Previous studies have shown that, in general, flu viruses in the tropics tend to be more diverse and circulate all year round rather than seasonally as happens with the strains of influenza virus in temperate regions, which have more moderate climates. According to the accepted theory so far, the new strains of seasonal influenza virus derived from the tropical areas of the world. Read the rest of this entry »
A research team led by scientists at the Institute for Research in Biomedicine (IRB Barcelona) has determined how the Ler protein, found in pathogenic bacteria, interacts with specific sequences of DNA by activating numerous genes responsible for virulence of bacteria used to infect human cells.
Ler is present in strains of Escherichia Coli (E. Coli) as which caused lethal infection in Germany the month of May. The work has been published in scientific journal PLoS Pathogens.
Researchers have revealed the three dimensional structure of a key region of the protein in complex with DNA. Knowing the structures that control the function of genes associated with virulence and / or resistance to antibiotics is essential to understand the molecular mechanisms that control bacterial pathogenicity and open the door to alternative treatments to conventional antibiotics. Read the rest of this entry »
Salmonellosis is one of the most common types of food poisoning induced by Salmonella bacteria, commonly known as salmonella. Each year, no less than 100 million people are infected worldwide.
This is the main cause of gastroenteritis and typhoid fever. Until recently, it was thought that the only human being was infected by eating contaminated products of animal origin (meat, eggs, milk etc.). However, there has been a significant increase in the last ten years of people infected with salmonella that had ingested raw vegetables.
Subsequent investigations indicated that contaminated fruits and vegetables should also be considered as vehicles of salmonella in humans. Now a team of researchers from INRA, CNRS, both in France Read the rest of this entry »
Wastewater is an ecosystem for discovering the virus that so far not been identified. This is one of the main conclusions of a study published in the journal MBIO involving experts of the Laboratory of Water and Food Viral Pollution of the UB and the Washington University.
The work, pioneered the application of metagenomics to viruses of wastewater, reveals that the viral universe is much more extensive than previously thought. At present only known virus 3000 and it is believed that most of those in nature have not been characterized. Read the rest of this entry »
A new study reveals up to what distance can travel the airborne microbes and until what extent this depends on the size of each microbe. The aerial dispersal ability of microorganisms is an important issue to certain epidemics.
The researchers, from Liverpool John Moores University in United Kingdom, the Swiss Federal Institute for Forest and other institutions, they used extensive digital models to study Earth’s atmosphere would be dispersed far microbes.
The team led by Dr Dave Wilkinson of Liverpool John Moores University and Symeon Koumoutsaris from the International Institute of Space Sciences in Bern, Switzerland, adapted models were originally designed to study the dispersion of dust particles. Read the rest of this entry »
An analysis of traces of ancient DNA from plankton in the sediments of the Black Sea has revealed that the same genetic stocks of virus and algae which remains may persist and coexist for centuries.
The results of this research may have implications for the valuations are made on the degree of ecological importance of viruses in the formation of ocean ecosystems, and perhaps that of freshwater.
Moreover, the finding that DNA viruses and the algae from the remaining can be preserved in the geologic record is of great interest to microbial ecologists, such as value Marco Coolen of Oceanographic Institution in Woods Hole, United States. Having that information in the geological record provides unprecedented insight into the long-term population dynamics of algae and viruses, separately and jointly. Read the rest of this entry »
A process analogous to sexual contact is established between certain flu viruses, can produce offspring, i.e., new influenza virus, resulting from the combination of the two “parents”, and the potential to trigger an epidemic that affects the Human Being.
Of course, viruses are not really capable of reproducing sexually between them, but sexual reproduction serves as a metaphor to explain some features of the biological process known as reassortment.
In the reorganization, two viruses enter the same cell, their genetic material is mixed, and there are new viruses are genetically different. Read the rest of this entry »
Arch has been discovered in a hot spring in Nevada, United States, which has an enzyme that can digest cellulose at temperatures near the boiling point of water.
In fact, the enzyme that digests cellulose microbe reaches its highest level of activity at the temperature 109 degrees Celsius record, above the boiling point of water.
The hyperthermophilic microbe discovered in a pond at 95 degrees Fahrenheit geothermal, is the second member of the former group of archaea that possess this ability to digest cellulose above 80 degrees Celsius and survive and grow because of it. And the enzyme that makes it possible in this arch is the most tolerant to heat than has so far found in microbes that digest cellulose, including bacteria.
The new findings, by the team of Douglas S. Clark, Harvey W. Blanch and Melinda E. Clark of the University of California at Berkeley, and Frank T. Robb and Joel E. Graham of the University of Maryland, is part of a research-oriented analysis of microbes from hot springs and other extreme environments, searching for new enzymes for use in complex industrial processes, including production of biofuels from plant fibers difficult to digest. Read the rest of this entry »
Methane is a greenhouse gas which has the second greatest effect on climate, after carbon dioxide. The concentration of methane in the atmosphere has almost tripled in the last 150 years. Atmospheric methane is at least 20 times more potent than carbon dioxide in terms of greenhouse gases.
Besides being emitted by human activities, including agriculture, mining and the use of fossil fuels, methane is released into the atmosphere from wetlands and many other natural sources, which include cows and other ruminants. The contribution of the cows would be a simple story if not for the huge population of them there in the world as a result of livestock. It is easy to feed the human population, and more meat should be produced to prevent malnutrition of a large part of humanity. Read the rest of this entry »
A new study shows that intestinal microbial communities in humans, and a very diverse group of mammals, perform basic physiological functions are greatly influenced by the eating habits of animals, mainly if they are carnivores, herbivores or omnivores.
The researchers sequenced gut microbes in stool samples of 33 species of mammals living in the wild or in zoos in the U.S. cities of San Luis and San Diego. In addition to identifying the bacterial species residing in the intestines of mammals, characterized the gene present in each microbial community and the functions associated with each gene or group of genes. Read the rest of this entry »