Power Dynamics in Community-Based Participatory Research: A Multiple-Case Study Analysis of Partnering Contexts, Histories, and Practices.

Community-based participatory research has a long-term commitment to principles of equity and justice with decades of research showcasing the added value of power-sharing and participatory involvement of community members for achieving health, community capacity, policy, and social justice outcomes. Missing, however, has been a clear articulation of how power operates within partnership practices and the impact of these practices on outcomes. The National Institutes of Health-funded Research for Improved Health study (2009-2013), having surveyed 200 partnerships, then conducted seven in-depth case studies to better understand which partnership practices can best build from community histories of organizing to address inequities. The diverse case studies represented multiple ethnic-racial and other marginalized populations, health issues, and urban and rural areas and regions. Cross-cutting analyses of the qualitative results focus on how oppressive and emancipatory forms of power operate within partnerships in response to oppressive conditions or emancipatory histories of advocacy within communities. The analysis of power was conducted within each of the four domains of the community-based participatory research conceptual model, starting from how contexts shape partnering processes to impact short-term intervention and research outputs, and contribute to outcomes. Similarities and differences in how partnerships leveraged and addressed their unique contexts and histories are presented, with both structural and relational practices that intentionally addressed power relations. These results demonstrate how community members draw from their resilience and strengths to combat histories of injustice and oppression, using partnership principles and practices toward multilevel outcomes that honor community knowledge and leadership, and seek shared power, policy, and community transformation changes, thereby advancing health equity.

Bacterial populations active in metabolism of C1 compounds in the sediment of Lake Washington, a freshwater lake.

Active members of the bacterial community in the sediment of Lake Washington, with special emphasis on C1 utilizers, were identified by employing two complementary culture-independent approaches: reverse transcription of environmental mRNA and 16S rRNA combined with PCR (RT-PCR) and stable-isotope probing (SIP) of DNA with the 13C-labeled C1 substrates methanol, methylamine, formaldehyde, and formate. Analysis of RT-PCR-amplified fragments of 16S rRNA-encoding genes revealed that gammaproteobacterial methanotrophs belonging to Methylobacter and Methylomonas dominate the active methylotroph population, while only one other known methylotrophic lineage, Methylophilaceae, was detected via this approach. Analysis of RT-PCR-amplified functional genes, pmoA and fae, allowed detection of alphaproteobacterial (Methylosinus) and gammaproteobacterial (Methylobacter, Methylomonas, and Methylomicrobium) methanotrophs, methylotrophs of the genus Methylobacterium, and yet-unidentified proteobacteria. SIP experiments allowed detection of a broad variety of groups actively metabolizing C1 compounds. Comparisons between 16S rRNA gene pools amplified from [13C]DNA and from [12C]DNA revealed that the proportion of Methylophilus-related sequences increased in the presence of [13C]methanol, [13C]methylamine, and [13C]formaldehyde; Novosphingobium-related sequences were enriched in the presence of [13C]methanol; Gemmatimonadaceae-related sequences were enriched in the presence of [13C]formaldehyde and [13C]formate; and Xanthomonadaceae-related sequences were enriched in the presence of [13C]formate. Analysis of fae genes amplified from [13C]DNAs isolated from different microcosms revealed specific shifts in populations in response to a specific C1 compound: Methylosinus sequences dominated the [13C]methanol microcosm pool, and beta- and gammaproteobacterial sequences dominated the [13C]methylamine microcosm pool. The [13C]formaldehyde microcosm was dominated by betaproteobacterial sequences and by sequences of a nonaffiliated group, while the [13C]formate microcosm was dominated by alpha- and betaproteobacterial sequences. Overall, these data point toward the presence of a diverse population of active methylotrophs in Lake Washington sediments and toward the existence of yet-uncultivated organisms.

Labrys methylaminiphilus sp. nov., a novel facultatively methylotrophic bacterium from a freshwater lake sediment.

A new bacterial isolate from a methylamine enrichment culture is described, representing a novel species of facultatively methylotrophic bacteria. The non-motile bacterium is Gram-negative, replicates by budding and does not form endospores. The isolate utilizes methylated amines, as well as a variety of monosaccharides, disaccharides, amino acids, organic acids, aromatic compounds and alcohols as substrates, but does not utilize methanol. Growth factors are not required, although yeast extract stimulates growth. The major components of the fatty acid profile are C(18 : 1)omega7c, C(19 : 0) cyclo and C(16 : 0). The dominant cellular phospholipids are phosphatidyl acid, phosphatidylcholine and phosphatidylethanolamine. The G + C content of the DNA is 65.7 +/- 0.3 mol%. 16S rRNA gene-based phylogenetic analysis revealed that the novel isolate belongs to the alpha-Proteobacteria and is closely related to the only representative of the genus Labrys, Labrys monachus (97.4 % sequence similarity). However, the level of DNA-DNA relatedness with L. monachus is less than 3 %, justifying the placement of this isolate into a novel species of the genus Labrys. The name Labrys methylaminiphilus sp. nov. is proposed (type strain JLW10(T) = ATCC BAA-1080(T) = DSM 16812(T)).