Infectious disease in the ancient Aegean: Intestinal parasitic worms in the Neolithic to Roman Period inhabitants of Kea, Greece

Little is known about infectious disease and parasites in the prehistoric inhabitants of the islands of the Aegean, in contrast to later time periods. It is only with the development of Greek medical texts in the 5th and 4th centuries BC we start to find evidence for the diseases that affected the population of region. Foremost amongst these authors was the medical practitioner Hippocrates, who lived on the island of Kos. The descriptions of the many diseases he and his students encountered were recorded in their medical texts in the 4th and 3rd centuries BC, known as the Hippocratic Corpus. These important texts provided the core philosophy underpinning medical theories in Europe and the Arab world for the following 2,000 years. Past research to determine which species of intestinal parasitic worms were described in the Hippocratic Corpus has suggested they indicate roundworm, pinworm and Taenia tapeworm. However, until now, there has been no archaeological evidence for which species of helminths were present in ancient Greece. In this study, we analysed soil sediment adherent to the sacrum and iliac bones of the pelvis of 25 burials dating from the Neolithic to Byzantine period on the Greek island of Kea, not far from Kos. Four individuals (16%) were positive for the eggs of intestinal helminths, dating from the Neolithic (4th millennium BC), Late Bronze Age, and the Roman Period. The species identified were whipworm (Trichuris trichiura) and roundworm (Ascaris lumbricoides). We consider reasons as to why fewer species of parasite appear to have been present on Kea than was the case for northern Europe at the same time period. This study of ancient parasites shows how we can combine archaeology with history of medicine to better understand the discoveries of key early scientists and medical practitioners

The genetic prehistory of southern Africa

Southern and eastern African populations that speak non-Bantu languages with click consonants are known to harbour some of the most ancient genetic lineages in humans, but their relationships are poorly understood. Here, we report data from 23 populations analyzed at over half a million single nucleotide polymorphisms, using a genome-wide array designed for studying human history. The southern African Khoisan fall into two genetic groups, loosely corresponding to the northwestern and southeastern Kalahari, which we show separated within the last 30,000 years. We find that all individuals derive at least a few percent of their genomes from admixture with non-Khoisan populations that began approximately 1,200 years ago. In addition, the east African Hadza and Sandawe derive a fraction of their ancestry from admixture with a population related to the Khoisan, supporting the hypothesis of an ancient link between southern and eastern AfricaComment: To appear in Nature Communication

Beta-lactam antibiotics: from antibiosis to resistance and bacteriology

This review focuses on the era of antibiosis that led to a better understanding of bacterial morphology, in particlar the cell wall component peptidoglycan. This is an effort to take readers on a tour de force from the concept of antibiosis, to the serepidity of antibiotics, evolution of betalactam development, and the molecular biology of antibiotic resistance. These areas of research have culminated in a deeper understanding of microbiology, particularly in the area of bacterial cell wall synthesis and recycling. In spite of this knowledge, which has enabled design of new even more effective therapeutics to combat bacterial infection and has provided new research tools, antibiotic resistance remains a worldwide health care problem

Steady-state kinetics and inhibition of anaerobically purified human homogentisate 1,2-dioxygenase

HGO (homogentisate 1,2-dioxygenase; EC 1.13.11.5) catalyses the O(2)-dependent cleavage of HGA (homogentisate) to maleylacetoacetate in the catabolism of tyrosine. Anaerobic purification of heterologously expressed Fe(II)-containing human HGO yielded an enzyme preparation with a specific activity of 28.3± 0.6 μmol·min(−1)·mg(−1) (20 mM Mes, 80 mM NaCl, pH 6.2, 25 °C), which is almost twice that of the most active preparation described to date. Moreover, the addition of reducing agents or other additives did not increase the specific activity, in contrast with previous reports. The apparent specificity of HGO for HGA was highest at pH 6.2 and the steady-state cleavage of HGA fit a compulsory-order ternary-complex mechanism (K(m) value of 28.6±6.2 μM for HGA, K(m) value of 1240±160 μM for O(2)). Free HGO was subject to inactivation in the presence of O(2) and during the steady-state cleavage of HGA. Both cases involved the oxidation of the active site Fe(II). 3-Cl HGA, a potential inhibitor of HGO, and its isosteric analogue, 3-Me HGO, were synthesized. At saturating substrate concentrations, HGO cleaved 3-Me and 3-Cl HGA 10 and 100 times slower than HGA respectively. The apparent specificity of HGO for HGA was approx. two orders of magnitude higher than for either 3-Me or 3-Cl HGA. Interestingly, 3-Cl HGA inactivated HGO only twice as rapidly as HGA. This contrasts with what has been observed in mechanistically related dioxygenases, which are rapidly inactivated by chlorinated substrate analogues, such as 3-hydroxyanthranilate dioxygenase by 4-Cl 3-hydroxyanthranilate