Starch-rich plant foods 780,000 y ago: Evidence from Acheulian percussive stone tools.

In contrast to animal foods, wild plants often require long, multistep processing techniques that involve significant cognitive skills and advanced toolkits to perform. These costs are thought to have hindered how hominins used these foods and delayed their adoption into our diets. Through the analysis of starch grains preserved on basalt anvils and percussors, we demonstrate that a wide variety of plants were processed by Middle Pleistocene hominins at the site of Gesher Benot Ya'aqov in Israel, at least 780,000 y ago.

Molecular properties of the RmlT wall teichoic acid rhamnosyltransferase that modulates virulence in Listeria monocytogenes.

Wall teichoic acids (WTAs) from the major Gram-positive foodborne pathogen Listeria monocytogenes are peptidoglycan-associated glycopolymers decorated by monosaccharides that, while not essential for bacterial growth, are required for bacterial virulence and resistance to antimicrobials. Here we report the structure and function of a bacterial WTAs rhamnosyltransferase, RmlT, strictly required for L. monocytogenes WTAs rhamnosylation.

Signals behind virulence mechanisms.

The tight and coordinated regulation of virulence gene expression is crucial to ensure the survival and persistence of bacterial pathogens in different contexts within their hosts. Considering this, bacteria do not express virulence factors homogenously in time and space, either due to their associated fitness cost or to their detrimental effect at specific infection stages. To efficiently infect and persist into their hosts, bacteria have thus to monitor environmental cues or chemical cell-to-cell signaling mechanisms that allow their transition from the external environment to the host, and therefore adjust gene expression levels, intrinsic biological activities, and appropriate behaviors.

Src-Dependent NM2A Tyrosine Phosphorylation Regulates Actomyosin Remodeling.

Non-muscle myosin 2A (NM2A) is a key cytoskeletal enzyme that, along with actin, assembles into actomyosin filaments inside cells. NM2A is fundamental for cell adhesion and motility, playing important functions in different stages of development and during the progression of viral and bacterial infections. Phosphorylation events regulate the activity and the cellular localization of NM2A.

Chasing iron bioavailability in the Southern Ocean: Insights from and iron speciation.

Dissolved iron (dFe) availability limits the uptake of atmospheric CO by the Southern Ocean (SO) biological pump. Hence, any change in bioavailable dFe in this region can directly influence climate. On the basis of Fe uptake experiments with , we show that the range of dFe bioavailability in natural samples is wider (<1 to ~200% compared to free inorganic Fe') than previously thought, with higher bioavailability found near glacial sources.