, 2011). Some of these factors are also produced by G217B (Holbrook E.D., Youseff B.H., and Rappleye C.A., pers. commun.). Finally, only NAm1 strains produce an extracellular serine-protease activity (Zarnowski et al., 2007a). No studies Rucaparib in vitro have been done to determine if any of these variations contribute to Histoplasma pathogenesis. The completion of genome sequences from multiple phylogenetic groups and the continued development and application of molecular genetic techniques are furthering our understanding of the pathogenic

mechanisms that underlie Histoplasma virulence. For two of the most studied strains, G186A and G217B, both conserved components (e.g., Cbp1, Sid1) and distinct factors (e.g., α-glucan, Yps3) shape the resultant pathogenesis (Table 1). Selleck Ruxolitinib The examples of AGS1 and YPS3 highlight the influence of dissimilar transcriptional regulation on variation between strains with highly similar genome sequences. Surprisingly few mechanistic studies have been performed with multiple

Histoplasma strains, making it difficult to extrapolate experimental results from one strain to the others. Based on the variation in the few virulence factors examined to date, additional aspects distinguishing Histoplasma strains are expected. Establishment of the relevance of such mechanistic differences to Histoplasma pathogenesis will require recognition of the dissimilarities between strains and performance of comparative studies using the molecular genetic tools now available. Research in the Rappleye lab is supported,

in part, by funding from the National Institutes of Health (research grant AI083335) and a T32 fellowship award AI654114 to J.E. “
“All diazotrophic filamentous cyanobacteria contain an uptake hydrogenase that is involved in the reoxidation of H2 produced during N2-fixation. In Nostoc punctiforme ATCC 29133, N2-fixation takes place in the microaerobic heterocysts, catalysed by a nitrogenase. Although the function of the uptake hydrogenase may be closely connected to that of nitrogenase, the localization in cyanobacteria has been under debate. Moreover, the subcellular localization next is not understood. To investigate the cellular and subcellular localization of the uptake hydrogenase in N. punctiforme, a reporter construct consisting of the green fluorescent protein (GFP) translationally fused to HupS, within the complete hupSL operon, was constructed and transferred into N. punctiforme on a self-replicative vector by electroporation. Expression of the complete HupS–GFP fusion protein was confirmed by Western blotting using GFP antibodies. The N. punctiforme culture expressing HupS–GFP was examined using laser scanning confocal microscopy, and fluorescence was exclusively detected in the heterocysts.