Physiological adaptation and population dynamics of a nitrifying sludge exposed to ampicillin.

Antibiotics in wastewater treatment plants can alter the physiological activity and the structure of microbial communities through toxic and inhibitory effects. Physiological adaptation, kinetic, and population dynamics behavior of a nitrifying sludge was evaluated in a sequential batch reactor (SBR) fed with 14.4 mg/L of ampicillin (AMP).

Stem transcriptome screen for selection in wild and cultivated pitahaya (: an epiphytic cactus with edible fruit.

Dragon fruit, pitahaya or pitaya are common names for the species in the group of that produce edible fruit. These Neotropical epiphytic cacti are considered promising underutilized crops and are currently cultivated around the world. The most important species, , has been managed in the Maya domain for centuries and is the focus of this article.

Long-term post-storage reactivation of a nitrifying sludge in a sequential batch reactor: physiological and kinetic evaluation.

Production, preservation and recovery of sludge with stabilized nitrifying activity over long time can be difficult. Information on the ability of nitrifying sludge to regain its nitrifying activity after long-term storage is still scarce. In this work, the physiological and kinetic changes during the reactivation and stabilization of a nitrifying sludge previously exposed to ampicillin (AMP) were evaluated in a sequential batch reactor (SBR) after its long-term storage (1 year) at 4 °C.

AGO104 is a RdDM effector of paramutation at the maize b1 locus.

Although paramutation has been well-studied at a few hallmark loci involved in anthocyanin biosynthesis in maize, the cellular and molecular mechanisms underlying the phenomenon remain largely unknown. Previously described actors of paramutation encode components of the RNA-directed DNA-methylation (RdDM) pathway that participate in the biogenesis of 24-nucleotide small interfering RNAs (24-nt siRNAs) and long non-coding RNAs. In this study, we uncover an ARGONAUTE (AGO) protein as an effector of the RdDM pathway that is in charge of guiding 24-nt siRNAs to their DNA target to create de novo DNA methylation.