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BackgroundCommon bean and cowpea contain about 25% protein and 25% fiber, and are recommended as complementary foods in sub-Saharan Africa.ObjectiveThe objective of this study was to determine if a daily legume supplement given to Malawian infants aged 6 to 12 mo alters the 16S configuration of the fecal microbiota as read out by amplicon sequence variants (ASVs).MethodsThis study was conducted within the context of a randomized, double-blind, controlled clinical trial to assess whether cowpea or common bean supplementation reduced intestinal permeability or increased linear growth. There were 2 village clusters in which the study was conducted. Fresh stool collections were flash frozen from 236 infants at ≤6 time points. The stools were sequenced using Earth Microbiome project protocols and data were processed using Qiime and Qiita, open-source, validated software packages. α-diversity was measured using the Faith's test. The 16S configuration was characterized by determining the weighted UniFrac distances of the ASVs and comparing them using permutational multivariate ANOVA.ResultsAmong the 1249 samples analyzed, the α-diversity of the fecal microbiome was unchanged among subjects after initiation of legume supplementation. Neither cowpea nor common bean altered the overall 16S configuration at any age. The 16S configuration differed between children with adequate and poor linear growth aged from 6 to 9 mo, but no specific ASVs differed in relative abundance. The 16S configuration differed between children with normal and abnormal intestinal permeability at 9 mo, but no specific ASVs differed in relative abundance. Among categorical characteristics of the population associated with different 16S configurations, village cluster was most pronounced.ConclusionLegume supplementation in breastfed, rural African infants did not affect the structure of the gut microbial communities until the children were aged 9 mo. This trial was registered at clinicaltrials.gov as NCT02472262.

Background & Aims: Environmental enteric dysfunction (EED), a chronic diffuse inflammation of the small intestine, is associated with stunting in children in the developing world. The pathobiology of EED is poorly understood because of the lack of a method to elucidate the host response. This study tested a novel microarray method to overcome limitation of RNA sequencing to interrogate the host transcriptome in feces in Malawian children with EED., Methods: In 259 children, EED was measured by lactulose permeability (%L). After isolating low copy numbers of host messenger RNA, the transcriptome was reliably and reproducibly profiled, validated by polymerase chain reaction. Messenger RNA copy number then was correlated with %L and differential expression in EED. The transcripts identified were mapped to biological pathways and processes. The children studied had a range of %L values, consistent with a spectrum of EED from none to severe., Results: We identified 12 transcripts associated with the severity of EED, including chemokines that stimulate T-cell proliferation, Fc fragments of multiple immunoglobulin families, interferon-induced proteins, activators of neutrophils and B cells, and mediators that dampen cellular responses to hormones. EED-associated transcripts mapped to pathways related to cell adhesion, and responses to a broad spectrum of viral, bacterial, and parasitic microbes. Several mucins, regulatory factors, and protein kinases associated with the maintenance of the mucous layer were expressed less in children with EED than in normal children., Conclusions: EED represents the activation of diverse elements of the immune system and is associated with widespread intestinal barrier disruption. Differentially expressed transcripts, appropriately enumerated, should be explored as potential biomarkers.

Rice transcription factor RF2a binds to the BoxII cis element of the promoter of rice tungro bacilliform virus and activates promoter expression. The acidic acid-rich domain of RF2a is a transcription activator and has been partially characterized (Dai et al., 2003). The RF2a acidic domain (A; amino acids 49-116) was fused with the synthetic zinc finger ZF-TF 2C7 and was co-introduced with a reporter gene into transgenic Arabidopsis plants. Expression of the reporter gene was increased up to seven times by the effector. In transient assays in tobacco BY-2 protoplasts, we identified a subdomain comprising amino acids 56-84 (A5) that was equally as effective as an activator as the entire acidic domain. A chemically inducible system was used to show determined that A and A5 domains are equally as effective in transcription activation as the well-characterized VP16 activation domain. Bioinformatics analyses revealed that the A5 domain is present only in b-ZIP transcription factors. In dicots, the A domain contains an insertion of four amino acids that is not present in monocot proteins. The A5 domain, and similar domains in other b-ZIP transcription factors, is predicted to form an anti-parallel beta sheet structure.