New Delhi: Using fragments extracted from the mummified remains of an Italian nobleman who died over 400 years ago, researchers have identified and reconstructed the first ancient genome of E. coli — bacteria commonly found in the intestines of healthy people and animals.
In a study published in the journal Communications Biology, an international team of researchers analysed the mummified remains of an Italian man who was 48 at the time of his death in 1586. The researchers were able to extract fragments of the common bacteria from what they believe was the man’s “chronic gallbladder inflammation from gallstones”.
While modern E. coli is harmless in most forms, some strains can cause serious — sometimes even fatal — food poisoning outbreaks and bloodstream infections.
The hardy and adaptable bacteria are characterised by their resistance to treatment and their evolutionary history remains a mystery, including when they acquired antibiotic resistance, according to researchers from Canada’s McMaster University.
Although it cannot become the cause of a pandemic, E. coli can act as an ‘opportunistic pathogen’, infecting its host in the presence of underlying disease or immunodeficiency.
Having the genome of a 16th-century ancestor to the modern bacterium provides researchers a point of comparison for studying how it has evolved and adapted over the centuries.
‘Porous solar cells could pave way for sponge-like pacemakers’
Scientists at the University of Chicago, US, have discovered a way to make porous solar cells, which they say could help in the development of less invasive, sponge-like pacemakers and other similar medical devices.
These soft, flexible cells — about the size of a red blood cell — made out of pure silicon, can be paired with optical fibre as thin as a strand of human hair to reduce the overall size of an implant, making it more body-friendly and less likely to cause side-effects.
The team credited with this innovation specialises in developing techniques to connect biological tissue and artificial materials such as wires, to modulate brain signals and surfaces for medical implants. Their paper has been published in Nature Materials.
Scientists at the Tian lab in the University of Chicago are now working on devices that can be powered by light from artificial sources. When operating in the body, such devices — known as photoelectrochemical cells — can be powered using a tiny optical fibre implanted in the body, replacing bulky batteries that accompany pacemakers.
Normally, solar cells require two layers, which can be achieved either by combining the silicon with another material such as gold, or by mixing different kinds of atoms into each silicon layer. But the team of scientists has created a solar cell out of pure silicon by making one layer porous.
Study explains how plants adapt to changes in climate
Plants can often make genetic ‘switches’ to change their functions and traits in order to adapt to changes in the local climate, a team of scientists from Pennsylvania State University has discovered.
The study, published in the journal Genome Biology, seeks to show that variations within plant genes can act as ‘switches’ that prompt changes in the RNA molecules.
The changes can affect a molecule’s stability, how it interacts with other molecules, and how efficiently it can be translated into protein — all of which can impact the plant’s function and traits.
According to the team of scientists, these genetic ‘switches’ allowed plants to adapt to their microclimates in the past and could be vital for future adaptation and the development of resilient crops amid climate change.
Fastest-growing black hole
Scientists claim to have found the fastest-growing black hole of the last 9 billion years. This black hole, they say, consumes the equivalent of one Earth every second and shines 7,000 times brighter than all of the light from our own galaxy — the Milky Way.
Among the most mysterious objects in the universe, black holes are millions and, sometimes, even billions of times larger than the Sun. Their gravitational pull is such that even light cannot escape.
In its findings, published in the Publications of the Astronomical Society of Australia, a team from the Australian National University (ANU) describes the black hole it found as a “very large, unexpected needle in the haystack”.
It is 500 times bigger than the black hole in our own galaxy.
With a mass of three billion Suns, this black hole continues to grow while others of a comparable size stopped growing at the same pace billions of years ago.
The black hole has a visual magnitude of 14.5 — a measure of how bright an object appears to an observer on Earth. This means that anyone with a decent telescope can see it comfortably.
Scientists are now trying to study why this black hole is so different from the others discovered so far.
‘Giant dwarf crocodiles’ roamed Earth millions of years ago
Scientists from the University of Iowa have discovered two new species of crocodiles — Kinyang mabokoensis and Kinyang tchernovi — that roamed east Africa between 18 million and 15 million years ago, preying on our human ancestors.
The species, called ‘giant dwarf crocodiles’, are related to dwarf crocodiles found in central and west Africa. However, the species mysteriously disappeared some 15 million years ago.
The dwarf crocodiles of today rarely exceed 4 or 5 feet in length, but their ancestors measured as long as 12 feet and were likely among the fiercest threats to any animal they encountered at the time.
According to the research team, these crocodiles may have been the biggest predators human ancestors faced in the prehistoric age. The giant dwarf crocodiles spent most of their time in the forest, rather than in the water, waiting to ambush prey, the team says.
They had short, deep snouts and large, conical teeth. Their nostrils opened “somewhat up and to the front”, not straight and upward as they do in the case of crocodiles we see today.
(Edited by Amrtansh Arora)