Bacteria are responsible for the delicious taste of salami, although industrial microbes do not yield as tasty dried sausages as wild microbes. PHOTO CREDIT: Tony Cenicola/NYT
How this sausage gets made
When you slice into a salami, you are enjoying the fruits of some very small organisms' labour. Like other dried sausages, salami is a fermented food. Its production involves a period where manufacturers allow microbes to work on the ground meat filling to create a bouquet of pungent, savoury molecules. Traditionally, the bugs find their way to the sausage from the surrounding environment. But these days, industrial manufacturers add a starter culture of bacteria to the meat instead.
A study published in the journal Applied Environmental Microbiology found that salami made with wild bugs scored higher with tasters than salami made with a starter culture. During the experiment, the researchers had a salami manufacturer create two batches. A starter was added to one batch and not to the other. Researchers saw an explosive growth in the starter bacteria. Very soon, they began to produce molecules that are usually made later. In contrast, a rainbow of species cropped up gradually in the other salami, generating a more complex - and apparently more pleasant - array of scent and flavour molecules.
Cold suns, warm exoplanets
Somewhere in our galaxy, an exoplanet is probably orbiting a star that's colder than our sun, but instead of freezing solid, the planet might be cosy warm thanks to a greenhouse effect caused by methane in its atmosphere. NASA astrobiologists from Georgia Institute of Technology, USA have developed a comprehensive new model that shows how planetary chemistry could make that happen.
The model, published in the journal Nature Geoscience, was based on a likely scenario on Earth three billion years ago. The new model combined multiple microbial metabolic processes with volcanic, oceanic and atmospheric activities, which may make it the most comprehensive of its kind to date.
Antibiotics constitute one of the most consequential medical advancements of the past century. We rely on them to battle infections and disease, and they're often the first line of defence in emergency rooms and physician offices across the globe. But what happens when they stop working? This may sound like an apocalyptic premise, but the warning signs are undeniable.
Antibiotic Resistance, produced by ABCTV Catalyst series, examines this oncoming crisis from the inside. The medical community is looking within and urging for more awareness in order to curb the liberal use of antibiotic drugs. Antibiotic Resistance takes us through various industries where researchers are working feverishly to combat this potential calamity. To watch the documentary, visit www.bit.ly/1rDkuRz.
Healing silk mats
Researchers at the Karnataka University, Dharwad have explored the wound healing properties of silk mats made from the silk of a wild species of silkworm, Antheraea mylitta (A. mylitta), commonly called the tasar silkworm. The study finds that tasar silk mats serve as a good scaffold in tissue engineering applications as it enables the attachment and growth of cells. The findings were published in the journal Scientific Reports.
In order to understand the physical, chemical and mechanical properties of silk mats made from A. mylitta, the researchers conducted a series of tests. They found that as compared to silk mats derived from Bombyx mori (B. mori), A. mylitta silk mats were less porous, more dense and had an almost continuous sheet of sericin, the protein which makes silk conducive to being a good scaffold material.
In addition, silk from A. mylitta had specific amino acids that facilitate greater cell attachment. The researchers then tested the new tasar silk mats as scaffolding to grow keratinocytes - a type of skin cell. Although the new silk mat was compatible with the cells, the densities of cells on the former were significantly higher. They also cultured cells on A. mylitta silk mats without the sericin content and found that now the cell densities were much lower than the untreated mats. This confirms that the presence of a high content of sericin is one of the features that enables A. mylitta silk mats to be good scaffolds.
High energy electrons
An international team of scientists have for the first time calculated the power radiated by high energy electrons in radio galaxies and galaxy clusters. When high energy electrons diffuse in the magnetic fields of a galaxy cluster or radio galaxy, it emits huge amounts of radio waves.
The amount of power radiated by this process however, still remains a mystery, as the lower limit of the electron energy distribution
is still not fully understood.
For their study, the scientists used a phenomenon called Sunyaev-Zel'dovich Effect to measure the lower limit of the momentum of the electron. By studying the amount of energy gained by the photons of the cosmic microwave background, the scientists could determine the lower limit.