Absentee Mothering – Not So Absent? Responses of European Rabbit (Oryctolagus cuniculus) Mothers to Pup Distress Calls

Longer‐range acoustic parent‐offspring communication is widespread, but might be absent in species in which young are hidden in burrows during the mother's absence. The European rabbit (Oryctolagus cuniculus) is such a species, with unusually limited maternal care largely restricted to a short daily nursing bout. Based, however, on evidence of frequent infanticide in this species, we hypothesize that rabbits possess a mechanism promoting a maternal response to pup distress calls. We conducted playback experiments with distress calls of pre‐weaning pups played next to the breeding burrows of mothers in a field enclosure (i.e. next to the burrows where mothers give birth and raise their young). Calls were played shortly after pups were born (T1) when infanticide risk is maximal, and shortly before the pups start dispersing from the breeding burrow (T2). A high proportion of mothers (60.6%) responded to pup calls by rapidly returning to their breeding burrow and 40% of them investigated the area around the entrance. Return responses to the playback of pup calls did not differ between mothers during T1 and T2. Thus, our results confirm that rabbit mothers respond rapidly to pup distress calls and that this responsiveness may adaptively serve to repel potentially infanticidal females.     

Expanding the Halohydrin Dehalogenase Enzyme Family: Identification of Novel Enzymes by Database Mining

Halohydrin dehalogenases are very rare enzymes that are naturally involved in the mineralization of halogenated xenobiotics. Due to their catalytic potential and promiscuity, many biocatalytic reactions have been described that have led to several interesting and industrially important applications. Nevertheless, only a few of these enzymes have been made available through recombinant techniques; hence, it is of general interest to expand the repertoire of these enzymes so as to enable novel biocatalytic applications. After the identification of specific sequence motifs, 37 novel enzyme sequences were readily identified in public sequence databases. All enzymes that could be heterologously expressed also catalyzed typical halohydrin dehalogenase reactions. Phylogenetic inference for enzymes of the halohydrin dehalogenase enzyme family confirmed that all enzymes form a distinct monophyletic clade within the short-chain dehydrogenase/reductase superfamily. In addition, the majority of novel enzymes are substantially different from previously known phylogenetic subtypes. Consequently, four additional phylogenetic subtypes were defined, greatly expanding the halohydrin dehalogenase enzyme family. We show that the enormous wealth of environmental and genome sequences present in public databases can be tapped for in silico identification of very rare but biotechnologically important biocatalysts. Our findings help to readily identify halohydrin dehalogenases in ever-growing sequence databases and, as a consequence, make even more members of this interesting enzyme family available to the scientific and industrial community.     

Effect of Fatigue on Hamstring Reflex Responses and Posterior-Anterior Tibial Translation in Men and Women

Anterior cruciate ligament (ACL) rupture ranks among the most common injuries in sports. The incidence of ACL injuries is considerably higher in females than in males and the underlying mechanisms are still under debate. Furthermore, it has been suggested that muscle fatigue can be a risk factor for ACL injuries.We investigated gender differences in hamstring reflex responses and posterior-anterior tibial translation (TT) before and after fatiguing exercise. We assessed the isolated movement of the tibia relative to the femur in the sagittal plane as a consequence of mechanically induced TT in standing subjects. The muscle activity of the hamstrings was evaluated. Furthermore, isometric maximum voluntary torque (iMVT) and rate of torque development (RTD) of the hamstrings (H) and quadriceps (Q) were measured and the MVT H/Q as well as the RTD H/Q ratios were calculated.After fatigue, reflex onset latencies were enhanced in women. A reduction of reflex responses associated with an increased TT was observed in females. Men showed no differences in these parameters. Correlation analysis revealed no significant associations between parameters for TT and MVT H/Q as well as RTD H/Q.The results of the present study revealed that the fatigue protocol used in this study altered the latency and magnitude of reflex responses of the hamstrings as well as TT in women. These changes were not found in men. Based on our results, it is conceivable that the fatigue-induced decrease in neuromuscular function with a corresponding increase in TT probably contributes to the higher incidence of ACL injuries in women.     

The PsbS protein controls the macro-organisation of photosystem II complexes in the grana membranes of higher plant chloroplasts

The PsbS protein is a critical component in the regulation of non-photochemical quenching (NPQ) in higher plant photosynthesis. Electron microscopy and image analysis of grana membrane fragments from wild type and mutant Arabidopsis plants showed that the semi-crystalline domains of photosystem II supercomplexes were identical in the presence and absence of PsbS. However, the frequency of the domains containing crystalline arrays was increased in the absence of PsbS. Conversely, there was a complete absence of such arrays in the membranes of plants containing elevated amounts of this protein. It is proposed that PsbS controls the macro-organisation of the grana membrane, providing an explanation of its role in NPQ.     

Transition metal-catalysed A-ring C–H activations and C(sp2)–C(sp2) couplings in the 13α-oestrone series and in vitro evaluation of antiproliferative properties

Facile syntheses of 3-O-carbamoyl, -sulfamoyl, or -pivaloyl derivatives of 13α-oestrone and its 17-deoxy counterpart have been carried out. Microwave-induced, Ni-catalysed Suzuki–Miyaura couplings of the newly synthesised phenol esters with phenylboronic acid afforded 3-deoxy-3-phenyl-13α-oestrone derivatives. The carbamate and pivalate esters proved to be suitable for regioselective arylations. 2-(4-Substituted) phenyl derivatives were synthesised via Pd-catalysed, microwave-assisted C–H activation reactions. An efficient, one-pot, tandem methodology was elaborated for the introduction of the carbamoyl or pivaloyl group followed by regioselective C-2-arylation and subsequent removal of the directing group. The antiproliferative properties of the novel 13α-oestrone derivatives were evaluated in vitro on five human adherent cancer cell lines of gynaecological origin. 3-Sulfamate derivatives displayed substantial cell growth inhibitory potential against certain cell lines. The newly identified antiproliferative compounds having hormonally inactive core might be promising candidates for the design of more active anticancer agents.     

Enhanced glutathione production by evolutionary engineering of Saccharomyces cerevisiae strains

Glutathione is an important natural tripeptide mainly used because of its antioxidative properties. Commercial glutathione is microbially synthesized by yeasts and the growing demand requires the development of new production strains. An adaptive laboratory evolution strategy using acrolein as a selection agent was employed to obtain strains with an enhanced glutathione accumulation phenotype accompanied by an acrolein resistance phenotype. Two particularly interesting isolates were obtained: one with a high volumetric productivity for glutathione reaching 8.3 mg_glutathione/L h, which is twice as high as the volumetric productivity of its parental strain. This strain reached an elevated intracellular glutathione content of 3.9%. A second isolate with an even higher acrolein tolerance exhibited a lower volumetric productivity of 5.8 mg_glutathione/L h due to a growth phenotype. However, this evolved strain accumulated glutathione in 3.3‐fold higher concentration compared to its parental strain and reached a particularly high glutathione content of almost 6%. The presented results demonstrate that acrolein is a powerful selection agent to obtain high glutathione accumulation strains in an adaptive laboratory evolution experiment.     

More than an empty case: a non invasive technique for monitoring the Australian critically endangered golden sun moth, Synemon plana (Lepidoptera: Castniidae)

Monitoring programs for butterflies and moths are focused on the adult stage, rarely considering other life stages. Transect-based counts of adults and searches for empty pupal cases have been suggested as standard monitoring protocols for the critically endangered golden sun moth Synemon plana in Australia. To date, surveys and monitoring have focused only on counts of adults. However, undertaking such counts is constrained by the short adult life of the species (1–2 days), and the fact that prevailing weather conditions can seriously influence detectability. We tested whether empty pupal cases of S. plana can be used to supplement the monitoring of adults and whether this technique can be undertaken by citizen scientists. Volunteers from Canberra (Australia) collected 650 pupal cases from 11 grassland areas. The cases were found in native grasslands and in grassland comprised entirely of the exotic Chilean needle grass (Nassella neesiana). Pupal cases of S. plana were found to be durable, with most persisting in the field for greater than 3 weeks after first sighting, and exhibited a male biased sex ratio. This study demonstrates that detection of empty pupal cases provides a potential additional tool to monitor S. plana that is not dependent on the restrictions of prevailing weather conditions and time of day, and can be undertaken by citizen scientists.