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Cadmium (Cd)-contaminated soil poses a severe threat to crop production and human health, while also resulting in a waste of land resources. In this study, two types of organic fertilizer (ZCK: Low-content available iron; Z2: High-content available iron) were applied to Cd-contaminated soil for rice cultivation, and the effects of the fertilizer on rice growth and Cd passivation were investigated in conjunction with soil microbial analysis. Results showed that Z2 could alter the composition, structure, and diversity of microbial communities, as well as enhance the complexity and stability of the microbial network. Both 2% and 5% Z2 significantly increased the fresh weight and dry weight of rice plants while suppressing Cd absorption. The 2% Z2 exhibited the best Cd passivation effect. Gene predictions suggested that Z2 may promote plant growth by regulating microbial production of organic acids that dissolve phosphorus and potassium. Furthermore, it is suggested that Z2 may facilitate the absorption and immobilization of soil cadmium through the regulation of microbial cadmium efflux and uptake systems, as well as via the secretion of extracellular polysaccharides. In summary, Z2 can promote rice growth, suppress Cd absorption by rice, and passivate soil Cd by regulating soil microbial communities. [Display omitted] • Organic fertilizers ZCK and Z2 can promote rice growth and inhibit Cd absorption. • Both ZCK and Z2 can passivate soil cadmium, and 2% Z2 has the best effect. • Microbial communities participate in cadmium passivation by regulating Cd-related genes. [ABSTRACT FROM AUTHOR]

Abstract Background Existing research typically focuses on only one domain of cognition with regard to fairness—theory of mind or executive function. However, children with High-functioning autism spectrum disorder (HF-ASD) are cognitively impaired in both domains. Moreover, little is known about fairness characteristics in children with HF-ASD in relation to both domains of cognition. Methods Thirty children with HF-ASD as well as 39 children with typical development (TD) were evaluated in this study. We investigated the development of children's fairness characteristics as a responder in a mini ultimatum game (UG). The different 'brain types,' i.e., with or without HF-ASD, were evaluated using the Empathy Questionnaire-Systemizing Questionnaire (E/SC-Q). Furthermore, we explored the relationship between fairness and brain types using Pearson correlation analyses. Results Children in the HF-ASD group were more likely to accept unfair offers than were children in the TD group (χ 2 = 17.513, p =.025). In the HF-ASD group, the acceptance rate of unfair offers was correlated with the discrepancy score (r = 0.363, p =.048), while there were no significant correlations in the TD group. In HF-ASD group, compared with Type S, acceptance rate of unfair offer was significant higher in Extreme Type S 'brain type' (F = 28.584, p <.001). While dividing TD participants by 'brain type', there was no significant difference in acceptance rate of unfair offer among five difference 'brain types' (F = 1.131, p =.358). Stepwise regression revealed that Extreme Type S positively predicted acceptance of unfair offers (F [1, 68] = 8.695, p <.001). Discussion Our findings show that children with HF-ASD were more likely to accept an unfair offer; in particular, the more unbalanced the development of empathy and systemizing was, the more significant the unfairness preference observed. Extreme Type S positively predicted the acceptance of unfair offers by children with HF-ASD. Registration of clinical trials World Health Organization class I registered international clinical trial platform, ChiCTR-ROC-17012877. Highlights • We examined the advanced cognitive function of ASD. • We enrolled children and adolescent as research participants. • We exploring the relationship between 'brain type' and fairness in children and adolescent with ASD. • We found fairness was related with the balance between empathy and systematizing in children and adolescent with ASD. [ABSTRACT FROM AUTHOR]

Due to the persistence of metals in the ecosystem and their threat to all living organisms, effects of heavy metal on soil microbial communities were widely studied. However, little was known about the interactions among microorganisms in heavy metal-contaminated soils. In the present study, microbial communities in Non (CON), moderately (CL) and severely (CH) contaminated soils were investigated through high-throughput Illumina sequencing of 16s rRNA gene amplicons, and networks were constructed to show the interactions among microbes. Results showed that the microbial community composition was significantly, while the microbial diversity was not significantly affected by heavy metal contamination. Bacteria showed various response to heavy metals. Bacteria that positively correlated with Cd, e.g. Acidobacteria_Gp and Proteobacteria_thiobacillus, had more links between nodes and more positive interactions among microbes in CL- and CH-networks, while bacteria that negatively correlated with Cd, e.g. Longilinea, Gp2 and Gp4 had fewer network links and more negative interactions in CL and CH-networks. Unlike bacteria, members of the archaeal domain, i.e. phyla Crenarchaeota and Euryarchaeota , class Thermoprotei and order Thermoplasmatales showed only positive correlation with Cd and had more network interactions in CH-networks. The present study indicated that (i) the microbial community composition, as well as network interactions was shift to strengthen adaptability of microorganisms to heavy metal contamination, (ii) archaea were resistant to heavy metal contamination and may contribute to the adaption to heavy metals. It was proposed that the contribution might be achieved either by improving environment conditions or by cooperative interactions. [ABSTRACT FROM AUTHOR]

Members of the Acidithiobacillus genus are widely found in extreme environments characterized by low pH and high concentrations of toxic substances, thus it is necessary to identify the cellular mechanisms needed to cope with these harsh conditions. Pan-genome analysis of ten bacteria belonging to the genus Acidithiobacillus suggested the existence of core genome, most of which were assigned to the metabolism-associated genes. Additionally, the unique genes of Acidithiobacillus ferrooxidans were much less than those of other species. A large proportion of Acidithiobacillus ferrivorans -specific genes were mapped especially to metabolism-related genes, indicating that diverse metabolic pathways might confer an advantage for adaptation to local environmental conditions. Analyses of functional metabolisms revealed the differences of carbon metabolism, nitrogen metabolism, and sulfur metabolism at the species and/or strain level. The findings also showed that Acidithiobacillus spp. harbored specific adaptive mechanisms for thriving under extreme environments. The genus Acidithiobacillus had the genetic potential to resist and metabolize toxic substances such as heavy metals and organic solvents. Comparison across species and/or strains of Acidithiobacillus populations provided a deeper appreciation of metabolic differences and environmental adaptation, as well as highlighting the importance of cellular mechanisms that maintain the basal physiological functions under complex acidic environmental conditions. [ABSTRACT FROM AUTHOR]

• For the first time, our study revealed the important role of circadian clock in rice response to chilling stress. • Nighttime-chilling stress affects leaf chlorophyll metabolism and PSII more severely than daytime-chilling stress. • The phase and amplitude of clock genes are regulated by chilling, suggesting interactions between clock and chilling stress. Chilling is a major abiotic stress affecting rice growth and development. Circadian clock is an endogenous timer enabling plants to cope with ever changing surroundings. However, little is known about coordination of circadian clock in rice chilling tolerance. In this study, we found that seedlings only subjected to nighttime-chilling stress exhibited chlorosis phenotype, with yellower leaves compared to those undergoing cold only at daytime. Chlorophyll content and photosynthesis efficiency in seedlings under nighttime-chilling stress were significantly lower than that under daytime-chilling stress. Transcriptome analysis distinguished the COLD-REGULATED (COR) genes between daytime and nighttime. COR genes responding differentially to daytime- and nighttime-chilling were non-randomly distributed among rice chromosomes, clustering mainly in 8 chromosome arms, Chr. 1L, 1S, 2L, 2S, 3L, 3S, 4L and 7L. Among them, key genes for chlorophyll metabolism and photosynthesis were repressed by chilling stress during Zeitgeber time (ZT) at night but promoted by stress during ZT time in day, which was confirmed by qRT-PCR. Our study revealed impacts of circadian clock on rice chilling response, implying that manipulation of circadian clock has great potential to determine the magnitude of chilling response, and would be helpful for breeding new rice varieties with chilling tolerance. [ABSTRACT FROM AUTHOR]

Bioleaching has been widely applied to recover sulfide minerals, however, little is known about the bioleaching behavior and mechanism of mixed oxide-sulfide copper ore with high-oxidative ratio. The leaching efficiency of artificial indigenous and exogenous microbial communities on a mixed oxide-sulfide copper ore with and without energy substrate was investigated. The results indicated that extra energy substrate was needed when bioleaching was applied to this kind of ore. The variation of leaching parameters caused by indigenous community was inferior to that caused by exogenous ones due to its lower activity. The leaching efficiency of sulfide part induced by indigenous strains was superior to that induced by exogenous ones, due to the stronger colonization ability of indigenous strains. It verified that both microbial activity and colonization ability were important properties affecting leaching efficiency. Sulfur oxidizers, which can oxidize sulfur or polysulfide formed on mineral surface and decrease leachate pH, played a more important role than ferrous oxidizers in bioleaching of high-oxidative oxide-sulfide ore. [ABSTRACT FROM AUTHOR]

The effect of co-culture microorganisms with different initial proportions on chalcopyrite bioleaching was investigated. Communities were rebuilt by six typical strains isolated from the same habitat. The results indicated, by community with more sulfur oxidizers at both 30 and 40 °C, the final copper extraction rate was 19.8% and 6.5% higher, respectively, than that with more ferrous oxidizers. The variations of pH, redox potential, ferrous and copper ions in leachate also provided evidences that community with more sulfur oxidizers was more efficient. Community succession of free and attached cells revealed that initial proportions played decisive roles on community dynamics at 30 °C, while communities shared similar structures, not relevant to initial proportions at 40 °C. X-ray diffraction analysis confirmed different microbial functions on mineral surface. A mechanism model for chalcopyrite bioleaching was established coupling with community succession. This will provide theoretical basis for reconstructing an efficient community in industrial application. [ABSTRACT FROM AUTHOR]

It is known that excess fines may reduce heap permeability and block channelings of leachate flow in heap bioleaching operation, and further cause low metal recovery. The purpose of this investigation was to compare the effects of three potential heap construction methods including layered heap construction method (Method A), agglomerate heap construction method (Method B) and pelletized sintering heap construction method (Method C) of copper flotation tailings on column bioleaching behaviors. In the three heap construction methods, the tailings copper extractions achieved 54.61%, 60.09% and 43.93%, respectively, in Method A, B and C on day 83. Copper extraction of Method B reached maximum. In addition, compositions and structures of microbial communities were examined using Illumina Miseq sequencing technology based on 16S rRNA amplification. Acidithiobacillus , Leptospirillum and Ferroplasma were main microorganisms in three heap construction methods. Detrended correspondence analysis showed that Method C had little effect on microbial communities. These studies revealed the influence of different heap construction methods on leaching behaviors and microbial dynamics, which will facilitate the bioleaching of fine-grained ores. [ABSTRACT FROM AUTHOR]

• Typical low-grade copper ores and their corresponding pure isolates were obtained. • Cross bioleaching of low-grade copper ores was firstly conducted. • Longitudinal domestication was an effective way to improve bioleaching performance. • Population regulation was another effective way to improve bioleaching efficiency. The interaction between microorganisms and minerals was a hot topic to reveal the transformation of key elements that affecting bioleaching efficiency. Three typical low-grade copper ores, the main copper-bearing components of which were primary sulfide, secondary sulfide and high-oxidative sulfide copper, were obtained from Dexing, Zijinshan and Luanshya copper mine, respectively. Meanwhile, six typical microorganisms were isolated from each of the three habitats, and assembled as communities based on their origins. Cross bioleaching was carried out under identical conditions. The leaching parameters showed that native strains played excellent roles in their corresponding ore bioleaching process, and community structure was greatly determined by mineral composition, indicating that domestication for longitudinal adaption was an effective way to improve microbial leaching performance. Leptospirillum ferriphilum and Acidithiobacillus ferrooxidans promoted copper release by shifting redox potential and pH of the leachate, respectively, indicating that microbial population regulation was another effective way to improve bioleaching efficiency. [ABSTRACT FROM AUTHOR]

Diverse metabolic behaviors endow microorganisms with various ecological functions, and metabolic activities of microbial species may affect the environmental conditions of their habitats. In this study, genome-guided analysis of Planktothrix spp. first divided these strains into six distinct groups, and comparisons of Planktothrix genomes revealed the inter- and intra-species variation. Prediction of central metabolism showed the functional diversity with regard to uptake of carbon, nitrogen, and sulfur sources. As the carbon-fixing microorganisms, Planktothrix isolates played a critical role in transforming the atmospheric carbon into organic carbon-the waterbodies' pool of available carbon. Diazotrophic lifestyle in certain Planktothrix strains may provide valuable avenues for supporting the equilibrium community. Furthermore, genome mining supported the exploration of biosynthetic gene clusters dedicated to cyanobacterial natural products, mainly including non-ribosomal peptide, polyketide, cyanobactin, and microviridin. Notably, some Planktothrix strains had the potential to non-ribosomally synthesize the microcystin (MC), a potent cyclic heptapeptide toxin, and MC-mediated cycling might strengthen the association between MC-producing and MC-degrading microorganisms. In short, genome-wide study of Planktothrix strains advances our current understanding of their metabolic potential and especially ecological roles in shaping natural environments. Unlabelled Image • Genome-based phylogeny dividing Planktothrix strains used into six separate clades • A global comparison strongly showing the intra- and inter-species differentiation • Metabolic diversity potentially contributing to their various ecological roles • An interplay pattern probably suggesting nutrient recycling in aquatic environments [ABSTRACT FROM AUTHOR]