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11.
Zusammenfassung Das in der vorliegenden Arbeit mitgeteilte Tatsachenmaterial stützt sich auf eine Sammelreise, die von den Verfassern in der Zeit vom 28. August bis 8. Oktober 1950 durchgeführt wurde. Es war unser Ziel, einen Überblick über dieDrosophila-Fauna von Südwesteuropa zu gewinnen und die Ergebnisse zu vergleichen mit dem Artenbestand, der vonBurla (1951) für die Schweiz festgestellt ist. Es wurden total 20 636 Imagines der GattungDrosophila gefangen; sie verteilen sich auf 27 Spezies. Es wurde fast nur in Wildbiotopen gesammelt. Eine Reihe von Beobachtungen zur Biologie der verschiedenen Arten sind im allgemeinen Teil (I) mitgeteilt und diskutiert. Der II. Teil der Arbeit bringt eine Charakterisierung der Fangplätze und ihrer Sammelerträge in den verschiedenen Klima- und Vegetationszonen des bereisten Gebietes. Im speziellen III. Teil wird die Verbreitung jeder einzelnen Art angegeben und mit dem Vorkommen in der Schweiz und in andern Gebieten Europas verglichen.Mit 26 Textabbildungen.Ausgeführt mit Unterstützung der Georges und Antoine Claraz-Schenkung. 相似文献
12.
Bencsik JR Xiao D Blake JF Kallan NC Mitchell IS Spencer KL Xu R Gloor SL Martinson M Risom T Woessner RD Dizon F Wu WI Vigers GP Brandhuber BJ Skelton NJ Prior WW Murray LJ 《Bioorganic & medicinal chemistry letters》2010,20(23):7037-7041
Herein we report the discovery and synthesis of a novel series of dihydrothieno- and dihydrofuropyrimidines (2 and 3) as potent pan Akt inhibitors. Utilizing previous SAR and analysis of the amino acid sequences in the binding site we have designed inhibitors displaying increased PKA and general kinase selectivity with improved tolerability compared to the progenitor pyrrolopyrimidine (1). A representative dihydrothieno compound (34) was advanced into a PC3-NCI prostate mouse tumor model in which it demonstrated a dose-dependent reduction in tumor growth and stasis when dosed orally daily at 200 mg/kg. 相似文献
13.
Solar radiation and functional traits explain the decline of forest primary productivity along a tropical elevation gradient 下载免费PDF全文
Nikolaos M. Fyllas Lisa Patrick Bentley Alexander Shenkin Gregory P. Asner Owen K. Atkin Sandra Díaz Brian J. Enquist William Farfan‐Rios Emanuel Gloor Rossella Guerrieri Walter Huaraca Huasco Yoko Ishida Roberta E. Martin Patrick Meir Oliver Phillips Norma Salinas Miles Silman Lasantha K Weerasinghe Joana Zaragoza‐Castells Yadvinder Malhi 《Ecology letters》2017,20(6):730-740
One of the major challenges in ecology is to understand how ecosystems respond to changes in environmental conditions, and how taxonomic and functional diversity mediate these changes. In this study, we use a trait‐spectra and individual‐based model, to analyse variation in forest primary productivity along a 3.3 km elevation gradient in the Amazon‐Andes. The model accurately predicted the magnitude and trends in forest productivity with elevation, with solar radiation and plant functional traits (leaf dry mass per area, leaf nitrogen and phosphorus concentration, and wood density) collectively accounting for productivity variation. Remarkably, explicit representation of temperature variation with elevation was not required to achieve accurate predictions of forest productivity, as trait variation driven by species turnover appears to capture the effect of temperature. Our semi‐mechanistic model suggests that spatial variation in traits can potentially be used to estimate spatial variation in productivity at the landscape scale. 相似文献
14.
Ruben Hummelen Andrew D. Fernandes Jean M. Macklaim Russell J. Dickson John Changalucha Gregory B. Gloor Gregor Reid 《PloS one》2010,5(8)
Background
Women living with HIV and co-infected with bacterial vaginosis (BV) are at higher risk for transmitting HIV to a partner or newborn. It is poorly understood which bacterial communities constitute BV or the normal vaginal microbiota among this population and how the microbiota associated with BV responds to antibiotic treatment.Methods and Findings
The vaginal microbiota of 132 HIV positive Tanzanian women, including 39 who received metronidazole treatment for BV, were profiled using Illumina to sequence the V6 region of the 16S rRNA gene. Of note, Gardnerella vaginalis and Lactobacillus iners were detected in each sample constituting core members of the vaginal microbiota. Eight major clusters were detected with relatively uniform microbiota compositions. Two clusters dominated by L. iners or L. crispatus were strongly associated with a normal microbiota. The L. crispatus dominated microbiota were associated with low pH, but when L. crispatus was not present, a large fraction of L. iners was required to predict a low pH. Four clusters were strongly associated with BV, and were dominated by Prevotella bivia, Lachnospiraceae, or a mixture of different species. Metronidazole treatment reduced the microbial diversity and perturbed the BV-associated microbiota, but rarely resulted in the establishment of a lactobacilli-dominated microbiota.Conclusions
Illumina based microbial profiling enabled high though-put analyses of microbial samples at a high phylogenetic resolution. The vaginal microbiota among women living with HIV in Sub-Saharan Africa constitutes several profiles associated with a normal microbiota or BV. Recurrence of BV frequently constitutes a different BV-associated profile than before antibiotic treatment. 相似文献15.
Mutual information without the influence of phylogeny or entropy dramatically improves residue contact prediction 总被引:2,自引:0,他引:2
MOTIVATION: Compensating alterations during the evolution of protein families give rise to coevolving positions that contain important structural and functional information. However, a high background composed of random noise and phylogenetic components interferes with the identification of coevolving positions. RESULTS: We have developed a rapid, simple and general method based on information theory that accurately estimates the level of background mutual information for each pair of positions in a given protein family. Removal of this background results in a metric, MIp, that correctly identifies substantially more coevolving positions in protein families than any existing method. A significant fraction of these positions coevolve strongly with one or only a few positions. The vast majority of such position pairs are in contact in representative structures. The identification of strongly coevolving position pairs can be used to impose significant structural limitations and should be an important additional constraint for ab initio protein folding. AVAILABILITY: Alignments and program files can be found in the Supplementary Information. 相似文献
16.
Kallan NC Spencer KL Blake JF Xu R Heizer J Bencsik JR Mitchell IS Gloor SL Martinson M Risom T Gross SD Morales TH Wu WI Vigers GP Brandhuber BJ Skelton NJ 《Bioorganic & medicinal chemistry letters》2011,21(8):2410-2414
A novel series of spirochromane pan-Akt inhibitors is reported. SAR optimization furnished compounds with improved enzyme potencies and excellent selectivity over the related AGC kinase PKA. Attempted replacement of the phenol hinge binder provided compounds with excellent Akt enzyme and cell activities but greatly diminished selectivity over PKA. 相似文献
17.
Wenglowsky S Ahrendt KA Buckmelter AJ Feng B Gloor SL Gradl S Grina J Hansen JD Laird ER Lunghofer P Mathieu S Moreno D Newhouse B Ren L Risom T Rudolph J Seo J Sturgis HL Voegtli WC Wen Z 《Bioorganic & medicinal chemistry letters》2011,21(18):5533-5537
Structure-activity relationships around a novel series of B-Raf(V600E) inhibitors are reported. The enzymatic and cellular potencies of inhibitors derived from two related hinge-binding groups were compared and3-methoxypyrazolopyridine proved to be superior. The 3-alkoxy group of lead B-Raf(V600E) inhibitor 1 was extended and minimally affected potency. The propyl sulfonamide tail of compound 1, which occupies the small lipophilic pocket formed by an outward shift of the αC-helix, was expanded to a series of arylsulfonamides. X-ray crystallography revealed that this lipophilic pocket unexpectedly enlarges to accommodate the bulkier aryl group. 相似文献
18.
Information theory was used to identify nonconserved coevolving positions in multiple sequence alignments from a variety of protein families. Coevolving positions in these alignments fall into two general categories. One set is composed of positions that coevolve with only one or two other positions. These positions often display direct amino acid side-chain interactions with their coevolving partner. The other set comprises positions that coevolve with many others and are frequently located in regions critical for protein function, such as active sites and surfaces involved in intermolecular interactions and recognition. We find that coevolving positions are more likely to change protein function when mutated than are positions showing little coevolution. These results imply that information theory may be applied generally to find coevolving, nonconserved positions that are part of functional sites in uncharacterized protein families. We propose that these coevolving positions compose an important subset of the positions in an alignment, and may be as important to the structure and function of the protein family as are highly conserved positions. 相似文献
19.
Dempsey BR Wrona M Moulin JM Gloor GB Jalilehvand F Lajoie G Shaw GS Shilton BH 《Biochemistry》2004,43(29):9361-9371
The solution NMR structure of a 22-residue Zn(2+)-binding domain (ZBD) from Esherichia coli preprotein translocase subunit SecA is presented. In conjunction with X-ray absorption analysis, the NMR structure shows that three cysteines and a histidine in the sequence CXCXSGX(8)CH assume a tetrahedral arrangement around the Zn(2+) atom, with an average Zn(2+)-S bond distance of 2.30 A and a Zn(2+)-N bond distance of 2.03 A. The NMR structure shows that ND1 of His20 binds to the Zn(2+) atom. The ND1-Zn(2+) bond is somewhat strained: it makes an angle of approximately 17 degrees with the plane of the ring, and it also shows a significant "in-plane" distortion of 13 degrees. A comprehensive sequence alignment of the SecA-ZBD from many different organisms shows that, along with the four Zn(2+) ligands, there is a serine residue (Ser12) that is completely conserved. The NMR structure indicates that the side chain of this serine residue forms a strong hydrogen bond with the thiolate of the third cysteine residue (Cys19); therefore, the conserved serine appears to have a critical role in the structure. SecB, an export-specific chaperone, is the only known binding partner for the SecA-ZBD. A phylogenetic analysis using 86 microbial genomes shows that 59 of the organisms carry SecA with a ZBD, but only 31 of these organisms also possess a gene for SecB, indicating that there may be uncharacterized binding partners for the SecA-ZBD. 相似文献
20.
Jason W. Gloor Lata Balakrishnan Robert A. Bambara 《The Journal of biological chemistry》2010,285(45):34922-34931
FEN1 cleaves 5′ flaps at their base to create a nicked product for ligation. FEN1 has been reported to enter the flap from the 5′-end and track to the base. Current binding analyses support a very different mechanism of interaction with the flap substrate. Measurements of FEN1 binding to a flap substrate show that the nuclease binds with similar high affinity to the base of a long flap even when the 5′-end is blocked with biotin/streptavidin. However, FEN1 bound to a blocked flap is more sensitive to sequestration by a competing substrate. These results are consistent with a substrate interaction mechanism in which FEN1 first binds the flap base and then threads the flap through an opening in the protein from the 5′-end to the base for cleavage. Significantly, when the unblocked flap length is reduced from five to two nucleotides, FEN1 can be sequestered from the substrate to a similar extent as a blocked, long flap substrate. Apparently, interactions related to threading occur only when the flap is greater than two to four nucleotides long, implying that short flaps are cleaved without a threading requirement. 相似文献