Bacillus subtilis: a shocking message from a probiotic

How probiotics such as Bacillus subtilis exert a protective effect has been much debated. In this issue of Cell Host & Microbe, Fujiya et al. reveal that a B. subtilis quorum-sensing signal molecule, the competence- and sporulation-stimulating factor (CSF), is internalized via the mammalian oligopeptide transporter OCTN2, where it induces the heat shock protein Hsp27, which protects intestinal cells against oxidant-mediated tissue damage and loss of barrier function.     

Urban birds have broader environmental tolerance

Urbanization dramatically changes the composition and diversity of biotic communities. The characteristics distinguishing species that persist in urban environments, however, are poorly understood. Here we test the hypothesis that broadly adapted organisms are better able to tolerate urbanization, using a phylogenetically controlled, global comparison of birds. We compared elevational and latitudinal distributions of 217 urban birds found in 73 of the world's largest cities with distributions of 247 rural congeners to test the hypothesis that urban birds possess broader environmental tolerance. Urban birds had markedly broader environmental tolerance than rural congeners, as estimated by elevational and latitudinal distributions. Our results suggest that broad environmental tolerance may predispose some birds to thrive in urban habitats. The mechanisms mediating such environmental tolerance warrant further investigation, but probably include greater behavioural, physiological and ecological flexibility.     

1H, 13C, and 15N backbone resonance assignments of the carboxyl terminal domain of Connexin40

Connexin40 is a gap junction protein involved in cell communication in the heart and other tissues. The assignments of an important Connexin40 regulatory domain, the carboxyl terminus, will aid in identifying the types of inter- and intramolecular interactions that affect channel activity.     

The Genetics Society of Canada takes a flight with Drosophila to celebrate its 50th year

The Genetics Society of Canada (GSC) held its 50th Anniversary Celebration June 18-21, 2007 in the New Residence Hall of McGill University in Montreal in conjunction with the 9(th) Canadian Drosophila Research Conference (CanFly), which is held in odd-numbered years. The meeting was a huge success with nearly 200 participants, and outstanding research presentations from all parts of Canada and beyond. The Canadian Drosophila research community is very vibrant: there are approximately 50 research labs in the country that work entirely or mostly in the Drosophila system, and a search of FlyBase for Canadian addresses yields a total of 248.     

Rapid and sensitive liquid chromatography-tandem mass spectrometry method for the quantitation of colchicine in human plasma

A rapid and sensitive method to determine colchicine in human plasma by liquid chromatography-tandem mass spectrometry (LC-MS/MS) has been developed. Colchicine and the internal standard (I.S.), tegafur, were extracted from the matrix with n-hexane:dichloromethane:isopropanol (300:150:15, v/v/v) and separated by reversed-phase high-performance liquid chromatography (HPLC) using formic acid:10 mM ammonium acetate:methanol (1:49:75, v/v/v) as the mobile phase in a run time of 2.5 min. Detection was carried out by electrospray positive ionization mass spectrometry in the multiple-reaction monitoring (MRM) mode. The assay was linear in the concentration range 0.050-10 ng/ml with intra- and inter-day precision (as relative standard deviation (R.S.D.)) of <2 and <7%, respectively. The method was applied to a pharmacokinetic study of colchicine in healthy volunteers given an oral dose of 2.0 mg.     

A HPLC-mass spectrometric method suitable for the therapeutic drug monitoring of everolimus

We report here the validation of an HPLC-electrospray-tandem mass spectrometry method for the quantification of everolimus, an immunosuppressant drug. Whole blood samples (100 microl) were extracted by protein precipitation which involved sample pre-treatment with zinc sulphate followed by acetonitrile (containing internal standard, 40-O-(3'-hydroxy)propyl-rapamycin). HPLC was performed using a step-gradient at a flow rate of 0.6 ml/min on a Waters TDM C18 column (10 mm x 2.1mm I.D.) with a resultant chromatographic analysis time of 2 min. Mass spectrometric detection by selected reaction monitoring (everolimus m/z 975.5-->908.3; internal standard m/z 989.5-->922.3). The assay was linear from 0.5 to 40 microg/l (r2>0.994, n=11). The inter- and intra-day analytical recovery and imprecision for quality control samples (1.25, 12.5 and 30 microg/l) were 93.4-98.2% and <10.7%, respectively (n=10). At the lower limit of quantification (0.5 microg/l) the inter- and intra-day analytical recovery was 94.4-95.8% with imprecision of <14.1% (n=10). The absolute recovery of everolimus (6.5 microg/l) and internal standard (12.5 microg/l) was 96.5 and 88.3%, respectively (n=3). A comparison of our method against the mean of all HPLC methods for a series of samples from an external proficiency testing scheme revealed good correlation as shown by the regression analysis: y=0.973x+0.301 (r2=0.986, n=71). In conclusion, the method described is suited to the current requirements for therapeutic drug monitoring of everolimus.     

Proteomic patterns for classification of ovarian cancer and CTCL serum samples utilizing peak pairs indicative of post-translational modifications

Proteomic patterns as a potential diagnostic technology has been well established for several cancer conditions and other diseases. The use of machine learning techniques such as decision trees, neural networks, genetic algorithms, and other methods has been the basis for pattern determination. Cancer is known to involve signaling pathways that are regulated through PTM of proteins. These modifications are also detectable with high confidence using high-resolution MS. We generated data using a prOTOF mass spectrometer on two sets of patient samples: ovarian cancer and cutaneous t-cell lymphoma (CTCL) with matched normal samples for each disease. Using the knowledge of mass shifts caused by common modifications, we built models using peak pairs and compared this to a conventional technique using individual peaks. The results for each disease showed that a small number of peak pairs gave classification equal to or better than the conventional technique that used multiple individual peaks. This simple peak picking technique could be used to guide identification of important peak pairs involved in the disease process.     

Effects of antler breakage on mating behavior in male tule elk (<Emphasis Type="Italic">Cervus elaphus nannodes</Emphasis>)

Although antler size has been identified as a primary determinant of dominance, fighting success, and reproductive success in male cervids, >80% of the male tule elk (Cervus elaphus nannodes) in the Owens Valley, California, experience antler breakage. To determine the effect of antler breakage on male mating success, we recorded antler morphology, body size, and mating behavior of male elk throughout the rut. Antler breakage, regardless of severity, had no effect on male–male assessment, fighting success, or harem-holding status. The factor consistently associated with our indices of male mating success was not antler size but body size. Although antler size is frequently emphasized as a key factor in male dominance and social rank, this association may reflect the correlation between antler size and body size. In the Owens Valley, it appears that male elk are not assessing competitors based on antler morphology but on other characteristics. An erratum to this article can be found at