Tryptophansynthase in Phycomyces blakesleeanus Teil I: Eigenschaften des Enzyms

Tryptophan synthase in Phycomyces blakesleeanus. Part I: Characterization of the enzyme. Tryptophan synthase was tested in light grown 5 days old cultures of Phycomyces blakesleeanus. The test was carried out only by reaction 3 (indole + serine → tryptophan + water) of the tryptophan synthase. The K_m values for the substrates indole and serine were found to be 1.3 × 10^-4M and 1.0 × 10^-2M. Two K_m values (1.5 × 10^-8M and 1.0 × 10^-6M) for pyridoxal 5′-phosphate could be calculated from a Lineweaver-Burk plot. The transformation of the Lineweaver-Burk plot into the Hill plot resulted in a straight line with a rise of 0.35 for pyridoxal 5′-phosphate. At higher concentrations the end product tryptophan and indole-3-acetic acid inhibit the tryptophan synthase in vitro.     

Sympatric distribution of two cryptic bat species across Europe

The analysis of echolocation calls and mitochondrial DNA sequences recently revealed the existence of two cryptic bat species in Western Europe which were regarded as 'Pipistrellus pipistrellus' for more than 200 years. We now present data on acoustic and genetic characters across Europe including a novel genetic marker from the nuclear genome. Intraspecific variation of end frequencies of echolocation calls did not differ between geographic regions and only a little overlap existed between the two species. Nuclear and mitochondrial DNA sequences for the two species were highly divergent. No evidence was found for additional cryptic species in this group. With the exception of Scandinavia, both species occur across the whole of Europe and largely overlap in their range. The distribution of the species using echolocation calls at higher frequencies extends further north and the same species is also more common in the south along the Mediterranean Sea.     

Drug‐Resistant Human Staphylococcus Aureus in Sanctuary Apes Pose a Threat to Endangered Wild Ape Populations

Reintroduction of sanctuary apes to natural habitat is considered an important tool for conservation; however, reintroduction has the potential to endanger resident wild apes through the introduction of human pathogens. We found a high prevalence of drug‐resistant, human‐associated lineages of Staphylococcus aureus in sanctuary chimpanzees (Pan troglodytes) from Zambia and Uganda. This pathogen is associated with skin and soft tissue diseases and severe invasive infections (i.e. pneumonia and septicemia). Colonization by this bacterium is difficult to clear due to frequent recolonization. In addition to its pathogenic potential, human‐related S. aureus can serve as an indicator organism for the transmission of other potential pathogens like pneumococci or mycobacteria. Plans to reintroduce sanctuary apes should be reevaluated in light of the high risk of introducing human‐adapted S. aureus into wild ape populations where treatment is impossible. Am. J. Primatol. 74:1071‐1075, 2012. © 2012 Wiley Periodicals, Inc.