dnaB analog function associated with plasmid R100drd-1

Embracing Technology for Capacity Building in Mental Health: New Path, Newer Challenges

Technology driven capacity building initiatives are the way to break the barrier of shortage of mental health human resources in India. This new path, while is a welcome step, comes with its own set of challenges. In one prototypic project that is being implemented in Ramanagara District of Karnataka, a south Indian state, we encountered many such issues. They ranged from issues related to availability of dedicated space to set up the hub-studio, inconsistent internet connectivity (particularly in remote areas) and inadequate digital literacy among the grassroot community health workers who hail from villages. This article summarises these challenges and ends by looking into ways and means of overcoming them.

Overinitiation of chromosome and plasmid replication in a dna Acos mutant of Escherichia coli K12. Evidence for dnaA-dnaB interactions

The dnaAcos mutations are phenotypic suppressors of dnaAts46 that are co-transduced with dnaA, render the cell cold sensitive, and cause an excess of chromosome replication relative to cell mass when the cells are shifted from 42 degrees C to 32 degrees C. We have used pulse labelling and DNA-DNA hybridization to follow the effect of a temperature shift on the replication of the chromosome and of the plasmids pSC101, RTF-Tc, and lambda dv in such strains. After a shift of a dnaAcos strain from 42 degrees C to 32 degrees C (non-permissive temperature), initiation of the chromosome and replication of the plasmid pSC101 are stimulated, while the dnaA-independent plasmid RTF-Tc is not affected. The presence of pSC101 does not affect the level of overinitiation of the chromosome. The presence of lambda dv suppresses the cold sensitivity of dnaAcos mutants and allows the cells to grow at both 32 degrees C and 42 degrees C. The presence of lambda dv suppresses the overinitiation of chromosome and of pSC101 replication at 32 degrees C. Previous reports had shown that these suppressions involve an interaction between the dnaA product and the lambda P protein, which is also known to interact with dnaB. We show here that the mutant prophage P1 bac-crr, which produces high levels of a dnaB analogue, suppresses the dnaAcos phenotype, while wild type P1 does not. These results suggest that initiation involves interactions between the dnaA and dnaB products.

Introduction of the plasmid pKM101-associated muc genes into Saccharomyces cerevisiae

Bacteria-yeast shuttle plasmids containing the pKM101-associated muc genes were constructed by cloning an ARS TRP fragment into the plasmid pGW270 in both possible orientations. The insertion of Saccharomyces cerevisiae DNA into pGW270 had no effect on the mutator and protective phenotypes associated with the plasmid in Escherichia coli. Two such recombinant plasmids, pAA90 and pAA91 , were capable of efficient transformation of S. cerevisiae and were stably maintained in this organism. Hybridization experiments suggest that muc-specific mRNA was present in transformed yeast cells and a small amount was polyadenylated. The RNAs were not of a discrete size, all being smaller than the muc genes. The presence of the plasmid pAA91 , and to a lesser extent, pAA90 , in yeast resulted in a detectable increase in the reversion frequencies of three markers and in ultraviolet protection. These results are discussed in terms of studying the relationship of error-prone repair in bacteria and yeast and of developing improved yeast tester strains.