SummaryLincomycin (LIN)‐mediated inhibition of protein synthesis in chloroplasts prevents the greening of seedlings, represses the activity of photosynthesis‐related genes in the nucleus, including LHCB1.2, and induces the phenylpropanoid pathway, resulting in the production of anthocyanins. In genomes uncoupled (gun) mutants, LHCB1.2 expression is maintained in the presence of LIN or other inhibitors of early chloroplast development. In a screen using concentrations of LIN lower than those employed to isolate gun mutants, we have identified happy on lincomycin (holi) mutants. Several holi mutants show an increased tolerance to LIN, exhibiting de‐repressed LHCB1.2 expression and chlorophyll synthesis in seedlings. The mutations responsible were identified by whole‐genome single‐nucleotide polymorphism (SNP) mapping, and most were found to affect the phenylpropanoid pathway; however, LHCB1.2 expression does not appear to be directly regulated by phenylpropanoids, as indicated by the metabolic profiling of mutants. The most potent holi mutant is defective in a subunit of cellulose synthase encoded by IRREGULAR XYLEM 3, and comparative analysis of this and other cell‐wall mutants establishes a link between secondary cell‐wall integrity and early chloroplast development, possibly involving altered ABA metabolism or sensing.

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The present work deals with the identification of a patient with two liver abscesses containing two different strains of Entamoeba histolytica, as defined by chitinase gene plymorphisms.

Nitrogen (N) deficiency is one of the major constraints for potato (Solanum tuberosum L.) production, due to its shallow root system and poor capabilities of N mobilization from the deeper layers of the soil. The aim of this study was to elucidate plasma membrane (PM) proteins potentially involved in the tolerance towards N deficiency. We compared the PM proteome of the two potato cultivars 'Lambada' and 'Topas', contrasting in their N deficiency response under in vitro conditions. Using mass spectrometry we identified 65 proteins, which were differentially abundant in the two cultivars when submitted to N deficiency. Amongst those, candidate proteins were selected based on their potential to be involved in N transport under deficient conditions. Two members of the aquaporin family, StPIP1;1 and StPIP1;3, were studied in more detail. By means of a yeast growth assay we showed that these proteins do not facilitate transport of ammonia. The Arabidopsis (Arabidopsis thaliana) knockout mutants AtPIP1;1 and AtPIP1;3 showed a reduced N content and accumulation of anthocyanins under N deficiency. We conclude that PIP1;1 and PIP1;3 are indirectly involved in the N uptake under N deficient conditions and contribute to an increased N deficiency tolerance. Summary statement Root plasma membrane proteome profiling of two potato cultivars reveals the participation of the two members of the aquaporin family PIP1;1 and PIP1;3 in the cultivar specific response to nitrogen deficiency.

Cryptosporidium spp. are responsible for moderate to severe diarrhea, mainly in children and immunocompromised patients. Using ELISA, the recognition of synthetic peptides generated from the sequences of the Cryptosporidium parvum gp40 and gp15 proteins by serum IgM and IgG antibodies from patients infected (cases) with Cryptosporidium hominis, C. parvum, and Cryptosporidium canis, and uninfected individuals (controls) was evaluated. A statistically significant difference (p = 0.0025) was found in terms of the recognition of peptides A133 and A32 between cases and controls. Additional studies are necessary to understand the potential of these peptides as vaccine candidates.