Elevated CO2 and Warming Altered Grassland Microbial Communities in Soil Top-Layers.

As two central issues of global climate change, the continuous increase of both atmospheric CO2 concentrations and global temperature has profound effects on various terrestrial ecosystems. Microbial communities play pivotal roles in these ecosystems by responding to environmental changes through regulation of soil biogeochemical processes. However, little is known about the effect of elevated CO2 (eCO2) and global warming on soil microbial communities, especially in semiarid zones. We used a functional gene array (GeoChip 3.0) to measure the functional gene composition, structure, and metabolic potential of soil microbial communities under warming, eCO2, and eCO2 + warming conditions in a semiarid grassland. The results showed that the composition and structure of microbial communities was dramatically altered by multiple climate factors, including elevated CO2 and increased temperature. Key functional genes, those involved in carbon (C) degradation and fixation, methane metabolism, nitrogen (N) fixation, denitrification and N mineralization, were all stimulated under eCO2, while those genes involved in denitrification and ammonification were inhibited under warming alone. The interaction effects of eCO2 and warming on soil functional processes were similar to eCO2 alone, whereas some genes involved in recalcitrant C degradation showed no significant changes. In addition, canonical correspondence analysis and Mantel test results suggested that NO3-N and moisture significantly correlated with variations in microbial functional genes. Overall, this study revealed the possible feedback of soil microbial communities to multiple climate change factors by the suppression of N cycling under warming, and enhancement of C and N cycling processes under either eCO2 alone or in interaction with warming. These findings may enhance our understanding of semiarid grassland ecosystem responses to integrated factors of global climate change

Glycosylation on Spermatozoa, a Promise for the Journey to the Oocyte

Spermatozoa experience a long and tough transit in male and female genital tracts before successful fertilization. Glycosylation helps spermatogenesis, epididymal maturation, passing through cervical mucus, avoiding killing of the female immunologic system, and shaking hands between sperm and egg. Changes in glycosylations along the transit ensure that the right things happen at the right time and place on spermatozoa. Aberrant glycosylations on spermatozoa will negatively affect their fertility. Thus, we developed a lectin array method to examine the glycocalyx of spermatozoa, which will help observe glycosylations occurring on spermatozoa in a normal or abnormal conditions, such as spermatozoa with DEF126 mutation and poor freezability. Intriguingly, binding levels of ABA (Agaricus bisporus agglutinin), a lectin marking the inner layer of the glycocalyx, were changed in these subfertile spermatozoa, which indicates that the integrity of glycocalyx is critical for sperm fertility. In this chapter, we reviewed the impacts of glycosylations on sperm fertility, the lectin array method, and its potential application for sperm function assessment

Soluble fusion expression, characterization and localization of human β-defensin 6

Human -defensin 6 (DEFB106) is an antimicrobial peptide expressed in the epididymis, testis and lung, which indicates that DEFB106 may be involved in innate immunity and fertility. However, as a -defensin, this protein has not been well characterized. Using an intein-mediated fusion expression system, the recombinant DEFB106 was expressed and purified (yield, 3-5 mg/l) under optimized conditions. The purified protein was characterized using mass spectrometry and circular dichroism spectroscopy. The measured molecular weight was consistent with its theoretical value and the predominant secondary structure was -sheet, the common structure of -defensin family members. The purified DEFB106 showed antimicrobial activity against not only Escherichia coli (E. coli) and Candida albicans (C. albicans) SC5314, but also Staphylococcus aureus (S. aureus) CMCC26003. Furthermore, it exhibited a high affinity for heparin and lipopolysaccharide. In addition, it was determined that native DEFB106 was located in the epididymis, bone marrow and skin. These observations may aid in the determination of the physiological and pathological functions of DEFB106.OncologyMedicine, Research & ExperimentalSCI(E)[email protected]; [email protected]