Streptomycin biosynthesis in Streptomyces griseus II. Adjacent genomic location of biosynthetic genes and one of two streptomycin resistance genes

Abstract A new quinone was isolated from the thermophilic methane-oxidizing bacterium strain H-2; was eluted after ubiquinone-8 on reversed-phase high-performance liquid chromatography (HPLC). Proton-magnetic resonance spectroscopy revealed that one of the isoprene units of a side chain was changed to 4-methyl-3-isopentene. The position of the substituted isoprene unit was localized by MS/MS spectrometry. The new quinone was identified as 2,3-dimethoxy-5-methyl-6-geranylgeranyl- [4-methyl-3-isopentenyl]-farnesyl-1,4-benzoquinone.     

Clinical study to assess the immunogenicity and safety of a recombinant Pseudomonas aeruginosa OprF-OprI vaccine in burn patients

In a recent clinical trial we evaluated the safety and immunogenicity of a recombinant OprF-OprI vaccine consisting of the mature outer membrane protein I (OprI) and amino acids 190-342 of OprF of Pseudomonas aeruginosa in burn patients and compared the elicited antibodies with antibodies against tetanus as response to a simultaneous immunization given on the day of admission. Safety and immunogenicity of the vaccine had been tested before in healthy human volunteers as published in 1999. In this first clinical trial we immunized eight burn patients suffering from second or third degree burns involving between 35% and 55% of the body surface three times with 100 microg of the OprF-OprI vaccine. The vaccine was found to be very well tolerated. The patients did not show any serious side effects - and in particular no activation of the mediator cascade was observed. None of the subjects showed systemic P. aeruginosa infections during or after the treatment of their burns. The serological tests (ELISA) for detection of antibodies against P. aeruginosa and tetanus toxoid showed seroconversion for seven patients after inoculation. The data indicate that OprF-OprI can be a useful vaccine in the therapeutic management of burn injuries.     

Insights into the Genetic History of French Cattle from Dense SNP Data on 47 Worldwide Breeds

Background

Modern cattle originate from populations of the wild extinct aurochs through a few domestication events which occurred about 8,000 years ago. Newly domesticated populations subsequently spread worldwide following breeder migration routes. The resulting complex historical origins associated with both natural and artificial selection have led to the differentiation of numerous different cattle breeds displaying a broad phenotypic variety over a short period of time.

Methodology/Principal Findings

This study gives a detailed assessment of cattle genetic diversity based on 1,121 individuals sampled in 47 populations from different parts of the world (with a special focus on French cattle) genotyped for 44,706 autosomal SNPs. The analyzed data set consisted of new genotypes for 296 individuals representing 14 French cattle breeds which were combined to those available from three previously published studies. After characterizing SNP polymorphism in the different populations, we performed a detailed analysis of genetic structure at both the individual and population levels. We further searched for spatial patterns of genetic diversity among 23 European populations, most of them being of French origin, under the recently developed spatial Principal Component analysis framework.

Conclusions/Significance

Overall, such high throughput genotyping data confirmed a clear partitioning of the cattle genetic diversity into distinct breeds. In addition, patterns of differentiation among the three main groups of populations—the African taurine, the European taurine and zebus—may provide some additional support for three distinct domestication centres. Finally, among the European cattle breeds investigated, spatial patterns of genetic diversity were found in good agreement with the two main migration routes towards France, initially postulated based on archeological evidence.     

Epidemic Contact Tracing via Communication Traces

Traditional contact tracing relies on knowledge of the interpersonal network of physical interactions, where contagious outbreaks propagate. However, due to privacy constraints and noisy data assimilation, this network is generally difficult to reconstruct accurately. Communication traces obtained by mobile phones are known to be good proxies for the physical interaction network, and they may provide a valuable tool for contact tracing. Motivated by this assumption, we propose a model for contact tracing, where an infection is spreading in the physical interpersonal network, which can never be fully recovered; and contact tracing is occurring in a communication network which acts as a proxy for the first. We apply this dual model to a dataset covering 72 students over a 9 month period, for which both the physical interactions as well as the mobile communication traces are known. Our results suggest that a wide range of contact tracing strategies may significantly reduce the final size of the epidemic, by mainly affecting its peak of incidence. However, we find that for low overlap between the face-to-face and communication interaction network, contact tracing is only efficient at the beginning of the outbreak, due to rapidly increasing costs as the epidemic evolves. Overall, contact tracing via mobile phone communication traces may be a viable option to arrest contagious outbreaks.     

Association of Vitamin D Receptor Polymorphisms (FokI (Rs2228570), ApaI (Rs7975232), BsmI (Rs1544410), and TaqI (Rs731236)) with Gastric Cancer in a Kurdish Population from West of Iran

Background:The association of 1,25-dihydroxy vitamin D3 (1,25(OH)2D3) and its receptor, vitamin D receptor (VDR), with cancer types have been studied. However, there are controversial findings regarding the association of specific VDR polymorphisms with different kinds of cancers. In the current study, we investigated the association of VDR polymorphisms (Fok1 (rs2228570), ApaI (rs7975232), BsmI (rs1544410), and TaqI (rs731236)) with the risk of gastric cancer in a Kurdish population of Kermanshah in Iran for the first time. Methods:In this case-control study, the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was used in 99 gastric cancer patients and 100 healthy subjects as controls.Results:The frequencies of f (FokI), b (BsmI), t (TaqI), and a (ApaI) alleles were: 55.6%, 27.3%, 62.1%, and 44.95% in the patient group, respectively and 42%, 29.5%, 54.5%, and 46.0% in the control group, respectively. Analysis of the results indicated that there was a positive association between the frequency of FokI genotypes with gastric cancer risk (p= 0.021). However, no statistically significant association of BsmI, Taq1, and ApaI polymorphisms of VDR was detected in gastric patients when compared with healthy individuals.Conclusion:VDR-FokI polymorphism could increase the risk of GC development and predispose to the disease by mechanisms.Key Words: Gastric cancer, PCR-RFLP, Polymorphism, Vitamin D receptor     

Proacrosin/acrosin activity during spermiohistogenesis of the bull

Abstract. Acrosin and its zymogen form, proacrosin, were extracted from early and late spermatids, from ejaculated and epididymal spermatozoa ( caput, corpus , and cauda ) of the bull. Activity of proacrosin/acrosin and the time course of proacrosin activation were studied. It turned out that proacrosin/acrosin activity is first demonstrable in haploid spermatids, increases during spermiohistogenesis in the testis, and remains nearly constant in epididymal and ejaculated spermatozoa.     

Proacrosin/acrosin activity during spermiohistogenesis of the bull

Acrosin and its zymogen form, proacrosin, were extracted from early and late spermatids, from ejaculated and epididymal spermatozoa (caput, corpus, and cauda) of the bull. Activity of proacrosin/acrosin and the time course of proacrosin activation were studied. It turned out that proacrosin/acrosin activity is first demonstrable in haploid spermatids, increases during spermiohistogenesis in the testis, and remains nearly constant in epididymal and ejaculated spermatozoa.     

D614G Spike Mutation Increases SARS CoV-2 Susceptibility to Neutralization

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