The outer membrane of Gram-negative bacteria is an essential compartment containing a specific complement of lipids and proteins that constitute a protective, selective permeability barrier. Outer membrane β-barrel proteins are assembled into the membrane by the essential hetero-oligomeric BAM complex, which contains the lipoprotein BamE. We have identified a homologue of BamE, encoded by CC1365, which is located in the outer membrane of the stalked alpha-proteobacterium Caulobacter crescentus. BamE associates with proteins whose homologues in other bacteria are known to participate in outer membrane protein assembly: BamA (CC1915), BamB (CC1653) and BamD (CC1984). Caulobacter cells lacking BamE grow slowly in rich medium and are hypersensitive to anionic detergents, some antibiotics and heat exposure, which suggest that the membrane integrity of the mutant is compromised. Membranes of the ΔbamE mutant have normal amounts of the outer membrane protein RsaF, a TolC homologue, but are deficient in CpaC*, an aggregated form of the outer membrane secretin for type IV pili. ΔbamE membranes also contain greatly reduced amounts of three TonB-dependent receptors that are abundant in wild-type cells. Cells lacking BamE have short stalks and are delayed in stalk outgrowth during the cell cycle. Based on these findings, we propose that Caulobacter BamE participates in the assembly of outer membrane β-barrel proteins, including one or more substrates required for the initiation of stalk biogenesis.

Nonstandard grammatical forms are often present in the writing of deaf students that are rarely, if ever, seen in the writing of hearing students. With the implementation of Strategic and Interactive Writing Instruction (SIWI) in previous studies, students have demonstrated significant gains in high-level writing skills (e.g., text structure) but have also made gains with English grammar skills. This 1-year study expands on prior research by longitudinally examining the written language growth (i.e., writing length, sentence complexity, sentence awareness, and function words) of 29 deaf middle-school students. A repeated-measures analysis of variance with a between-subjects variable for literacy achievement level was used to examine gains over time and the intervention's efficacy when used with students of various literacy levels. Students, whether high or low achieving, demonstrated statistically significant gains with writing length, sentence complexity, and sentence awareness. Subordinate clauses were found to be an area of difficulty, and follow up strategies are suggested. An analysis of function word data, specifically prepositions and articles, revealed different patterns of written language growth by language group (e.g., American Sign Language users, oral students, users of English-based sign).

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This study evaluated the impact of participating in child-centered play therapy for qualifying diverse second-grade students, implemented through the Primary Mental Health Project treatment protocol. This preventative approach focuses on the behavioral, emotional, and social skills of children through child-centered play therapy. Second-grade students at 1 elementary school were assessed by their teachers for 4 types of behaviors: task orientation, behavior control, assertiveness, and peer/social skills. Results demonstrated significant improvement in all 4 areas assessed for students who qualified for and received services over the course of 1 academic year. Findings suggest that child-centered play therapy is an effective preventative approach for students who are at risk for developing adverse behaviors that could negatively impact their academic success. Implications and the importance of providing preventative intervention for at-risk children are discussed.