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A fenvalerate-degrading bacterial strain F-7 was isolated from long-term contaminated sludge. Based on morphological, physiological and biochemical characterization, and phylogenetic analysis of 16S rRNA gene sequence, strain F-7 was identified as Sphingomonas sp. The bacterium could utilize fenvalerate as the sole source of carbon. An amount measuring 100 mg L(-1) fenvalerate was completely degraded within 72 h and 3-phenoxybenzoic acid (3-PBA) was detected as a major metabolite. The result indicates that S. sp. F-7 might metabolize fenvalerate by hydrolysis of carboxylester linkage. It was capable of degrading permethrin, fenpropathrin, beta-cypermethrin, cyhalothrin, deltamethrin, bifenthrin and 3-PBA. Further studies demonstrated that the strain was multi-resistant to heavy metals and antibiotics. In addition, degradative enzymes involved were confirmed as intracellular distributed and constitutively expressed. Furthermore, application of the strain was found to accelerate the removal of fenvalerate in soil. This is the first report of fenvalerate degrading strain isolated from S. sp. These results might help with future research in better understanding of pyrethroid biodegradation and highlight S. sp. F-7 might have potential for practical application in bioremediation of fenvalerate-contaminated sites.

Several strategies have been used to generate transgenic birds. The most successful method so far has been the injection of lentiviral vectors into the subgerminal cavity of a newly laid egg. We report here a new, easy and effective way to produce transgenic quails through direct injection of a lentiviral vector, containing an enhanced-green fluorescent protein (eGFP) transgene, into the blood vessels of quail embryos at Hamburger-Hamilton stage 13–15 (HH13–15). A total of 80 embryos were injected and 48 G0 chimeras (60%) were hatched. Most injected embryo organs and tissues of hatched quails were positive for eGFP. In five out of 21 mature G0 male quails, the semen was eGFP-positive, as detected by polymerase chain reaction (PCR), indicating transgenic germ line chimeras. Testcross and genetic analyses revealed that the G0 quail produced transgenic G1 offspring; of 46 G1 hatchlings, 6 were transgenic (6/46, 13.0%). We also compared this new method with the conventional transgenesis using stage X subgerminal cavity injection. Total 240 quail embryos were injected by subgerminal cavity injection, of which 34 (14.1%) were hatched, significantly lower than the new method. From these hatched quails semen samples were collected from 19 sexually matured males and tested for the transgene by PCR. The transgene was present in three G0 male quails and only 4/236 G1 offspring (1.7%) were transgenic. In conclusion, we developed a novel bird transgenic method by injection of lentiviral vector into embryonic blood vessel at HH 13–15 stage, which result in significant higher transgenic efficiency than the conventional subgerminal cavity injection.

The estrogenic compound diethylstilbestrol (DES) has been widely studied to understand its potential involvement in endocrine function and carcinogenesis. This study examined the influence of DES on adult mice by histopathological analysis and studied the gene expression changes using mRNA differential display. Pathological changes in the mice following DES exposure included testicular atrophy, ovarian and hepatic fibrosis, and reduced numbers of mature oocytes and spermatogenic cells. Other pathological changes, such as cirrhosis of the liver, were also found. To elucidate the molecular mechanism underlying these effects, we used mRNA differential display to analyze changes in gene expression following DES exposure. In total, 20 genes were differentially expressed in liver, kidney, ovary, uterus, and testis. All putative target genes were validated by QRT-PCR. The study provides evidence that DES has an acute effect on gene expression. The results may facilitate the discovery of the genotoxic mechanism of DES and allow one to discover new DES-responsive genes.

Anthropogenic activities have weakened the invasion of ruderals and increased the number of non-native species in urban areas. Ruderals are an important component of urban plant diversity and are of great significance to the sustainable development of urban green space. We used the tessellation–randomized plot method to examine the composition and biodiversity of ruderal species among urban land use types (LUTs) in the built-up areas of Beijing. Soil samples from the surface to a depth of 10 cm were taken from each site to examine the impact of soil characteristics on ruderal species diversity. Results showed that a total of 120 ruderal species were observed, including 71 native and 49 non-native species. Among them, 90% were identified as Cosmopolitan. Native species accounted for the majority of ruderals across all the eight LUTs. Institutional, residential, and woodlot areas with coarser management had higher ruderal species richness than did commercial areas and roadside lawns. Allergenic species showed the highest proportions in municipal parks, and invasive species accounted for 20% of all ruderal species. Ruderal species diversity was related to distance from the urban center, pruning intensity, and soil characteristics. These results suggest that with ruderals playing an important role in urban grass species diversity, there is tremendous potential for more native species in Beijing lawns, which would contribute substantially to increasing the ecological system’s functional benefits. Ruderal species accustomed to the causal processes and environmental conditions of different LUTs should be used and conserved properly to improve the harsh conditions of different LUTs and to sustain ecosystem health.