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Heavy metal (HM) contamination and high environmental temperature (HT) are caused by anthropogenic activities that negatively impact soil microbial communities and agricultural productivity. Although HM contaminations have deleterious effects on microbes and plants; there are hardly any reports on the combined effects of HM and HT. Here, we reported that HT coupled with cadmium (Cd) accumulation in soil and irrigated water could seriously affect crop growth and productivity, alternatively influencing the microbial community and nutrient cycles of paddy soils in rice fields. We analyzed different mechanisms of plants and microflora in the rhizospheric region, such as plant rhizospheric nitrification, endophytes colonization, nutrient uptake, and physiology of temperature-sensitive (IR64) and temperature-resistant Huanghuazhan (HZ) rice cultivars against different Cd levels (2, 5 and 10 mg kg−1) with rice plants grown under 25 °C and 40 °C temperatures. Consequently, an increment in Cd accumulation was observed with rising temperature leading to enhanced expression of OsNTRs. In contrast, a greater decline in the microbial community was detected in IR64 cultivar than HZ. Similarly, ammonium oxidation, root-IAA, shoot-ABA production, and 16S rRNA gene abundance in the rhizosphere and endosphere were significantly influenced by HT and Cd levels, resulting in a significant decrease in the colonization of endophytes and the surface area of roots, leading to a decreased N uptake from the soil. Overall, the outcomes of this study unveiled the novel effects of Cd, temperature, and their combined effect on rice growth and functions of the microbial community. These results provide effective strategies to overcome Cd-phytotoxicity on the health of endophytes and rhizospheric bacteria in Cd-contaminated soil by using temperature-tolerant rice cultivars. [Display omitted] • Elevated temperature coupled with Cd toxicity reduced microbial colonization. • Positive relationship was observed among Cd, temperature and the expression of OsNTRs. • Higher temperature with Cd absorption caused decrease in nitrogen uptake from soil. • High temperature and Cd are detrimental to plant growth hormones and ultrastructure. [ABSTRACT FROM AUTHOR]

Objective: To investigate the role of serine-threonine phosphorylation on the activity of human P450c17.Design: In vitro study.Setting: Academic basic research laboratory.Patient(s): None.Intervention(s): P450c17 expression constructs with a FLAG-tag on either the C-terminus or N-terminus of the protein were generated. Human C-terminal FLAG-tagged P450c17 chromosomal DNA was subjected to site-directed mutagenesis. Serine 258 and threonine 260 each were mutated to alanine and aspartic acid. The mutant P450c17s were expressed in COS-7 cells, and the enzymatic activities were measured.Main Outcome Measure(s): 17alpha-Hydroxylase and C(17-20) lyase activities of human P450c17.Result(s): C-terminal FLAG-tagged P450c17 functioned indistinguishably from the wild-type P450c17. Mutants S258A, S258D, and T260D had significantly less 17alpha-hydroxylase and C(17-20) lyase activities than the wild type.Conclusion(s): Adding an epitope tag to the C-terminus of the P450c17 protein does not interfere with its activities and will be a useful tool to isolate human P450c17 protein from cultured cells. Phosphorylation of serine 258 but not threonine 260 may act as a physiologic regulator of both enzymatic activities through interaction with obligatory redox partners. [ABSTRACT FROM AUTHOR]

An NADP+-dependent alcohol dehydrogenase was found in Euglena gracilis Z grown on 1-hexanol, while it was detected at low activity in cells grown on ethanol or glucose as a carbon source, indicating that the enzyme is induced by the addition of 1-hexanol into the medium as a carbon source. This enzyme was extremely unstable, even at 4 °C, unless 20% ethylene glycol was added. The optimal pH was 8.8–9.0 for oxidation reaction. The apparent Km values for 1-hexanol and NADP+ were found to be 6.79 mM and 46.7 μM for this enzyme, respectively. The substrate specificity of this enzyme was very different from that of already purified NAD+-specific ethanol dehydrogenase by showing the highest activity with 1-hexanol as a substrate, followed by 1-pentanol and 1-butanol, and there was very little activity with ethanol and 1-propanol. This enzyme was active towards the primary alcohols but not secondary alcohols. Accordingly, since the NADP+-specific enzyme was separated on DEAE cellulose column, Euglena was confirmed to contain a novel enzyme to be active towards middle and long-chain length of fatty alcohols. [Copyright &y& Elsevier]

Contamination of heavy metals is a serious threat, which causes threats to the environment. Our study aimed to determine the role of endophytic bacteria in Cd phytoremediation and heavy metal ATPase gene expression. Cadmium (Cd) resistant endophytic bacteria were isolated from Solanum nigrum on LB agar plates, contaminated with 0–30 mg/L Cd. The phosphate solubilization and indole-3-acetic acid (IAA) production of endophytes were estimated by growing them on Pikovskaya agar medium and GC-MS analysis, respectively. An experiment in a pot was performed to evaluate the effects of bacteria on rice plants contaminated with 5–25 mg/L of Cd. Expression of Cd response genes was quantified through qRT–PCR and Cd translocation from one part to another part of the plant was measured through the ICP. BLAST alignment of 16 S-rDNA gene sequences confirmed the bacterial isolates as Serratia sp. AI001 and Klebsiella sp. Strain AI002. Both strains tolerated Cd up to 25 mg/L and produced 27–30 μg/mL of IAA. Inoculation of AI001 and AI002 improved plant growth dynamics (i.e., plant length, biomass, chlorophyll contents), relieved electrolyte leakage, and improved reduced glutathione significantly (P < 0.05). The inoculation of AI001 and AI002 significantly (P < 0.05) induced the expression of heavy metal ATPase genes ie., " HMA2, HMA3, and HMA4 " and Cd translocation compared to uninoculated plants. Both AI001 and AI002 exhibited very prominent plant-growth-promoting and Cd phytoremediation properties. The results revealed that isolates also contributed a lot to the expression of rice plant heavy metal ATPase genes and in the Cd translocation in the plant. [Display omitted] • Bacteria, isolated from the Solanum nigrum showed high Cd tolerance in LB medium. • Bacterial strain "AI001 and AI002" were identified through 16 S-rDNA sequencing. • AI001 and AI002 induced plant growth and phytoremediation compared to control. • Isolates induced the expression of HMAs genes in plants exposed to Cd. • Translocation of Cd from roots to shoots in plants was enhanced by isolates. [ABSTRACT FROM AUTHOR]

Objective: To determine changes in adrenal androgen (AA) production, and transcription of dehydroepiandrosterone (DHEA) sulfotransferase (SULT2A1) in the NCI-H295R human adrenocortical cell line in response to insulin and testosterone, an environment mimicking the polycystic ovary syndrome state.Design: In vitro experiment using NCI-H295R adrenocortical cell lines.Setting: Academic medical center.Patient(s): NCI-H295R human adrenocortical cell line.Intervention(s): The transcriptional activity of SULT2A1 and adrenal steroid production was quantified after exposure to various treatments (e.g., forskolin, insulin, testosterone, and combinations thereof).Main Outcome Measure(s): Quantification of mRNA for DHEA sulfotransferase (SULT2A1) by real-time reverse transcription-polymerase chain reaction and measurement of steroid production by radioimmunoassay.Result(s): Testosterone decreased DHEAS and cortisol, and increased DHEA secretion by H295R cells; the inhibitory effects of testosterone on DHEAS and cortisol production were augmented by insulin. There was a trend toward an increase in the transcription of SULT2A1 by insulin and testosterone.Conclusion(s): Testosterone and insulin appear to be modulators of adrenal androgen production in this human adrenocortical cell model. These results suggest that testosterone may augment DHEA secretion in the human adrenal, although they do not support the role of this sex steroid or insulin on the elevated DHEAS levels frequently observed in polycystic ovary syndrome. [ABSTRACT FROM AUTHOR]