Distinctive variations in whole spore morphology and spore surface morphology of Streptomyces hygroscopicus strains, which had been observed previously by the authors by the preshadowed carbon replica technique, were confirmed by observations with the scanning electron microscope.

Microsporidia are obligate intracellular opportunistic protists that infect a wide variety of animals, including humans, via environmentally resistant spores. Infection requires that spores be in close proximity to host cells so that the hollow polar tube can pierce the cell membrane and inject the spore contents into the cell cytoplasm. Like other eukaryotic microbes, microsporidia may use spe...

Most mosses have xerochastic dispersal (i.e., they open their capsules when conditions are dry), which is thought to favor long-distance dispersal. However, there are several species that use a hygrochastic strategy: spores are dispersed when conditions are wet. The significance of this strategy in the Mediterranean region is unknown. In this study, we explored whether ultrastructural features ...

An optimized strategy for the enhancement of microbially induced calcium precipitation including spore viability ensurance, nutrient selection and O2 supply was developed. Firstly, an optimal yeast extract concentration of 5 g/l in sporulation medium was determined based on viable spore yield and spore viability. Furthermore, the effects of certain influential factors on microbial calcium preci...

Microsporidia constitute a large group of obligate intracellular protozoan parasites that inject themselves into host cells via the extrusion apparatus of the infective spore stage. Although the injection process is poorly understood, its energy source is thought to reside in the posterior vacuole that swells significantly during spore firing. Here we report the presence and localisation of the...

The forcibly launched spores of ascomycete fungi must eject through several millimeters of nearly still air surrounding fruiting bodies to reach dispersive air flows. Because of their microscopic size, spores experience great fluid drag, and although this drag can aid transport by slowing sedimentation out of dispersive air flows, it also causes spores to decelerate rapidly after launch. We hyp...

We sought to identify proteins in the Bacillus anthracis spore, conserved in other strains of the closely related Bacillus cereus group, that elicit an immune response in mammals. Two high throughput approaches were used. First, an in silico screening identified 200 conserved putative B. anthracis spore components. A total of 192 of those candidate genes were expressed and purified in vitro, 75...

Fructose 1,6-diphosphate aldolase from cells of Bacillus cereus appears to be typical Class II aldolase as judged by its functional and physical properties. Spore and vegetative cell aldolase had similar enzymatic, immunochemical, and heat resistance properties in the absence of calcium, but they differed in their thermal stabilities in the presence of calcium, their Stokes' radii, their mobili...

The SMK1 mitogen-activated protein kinase is required for spore morphogenesis in Saccharomyces cerevisiae. In contrast to the multiple aberrant spore wall assembly patterns seen even within a single smk1 null ascus, different smk1 missense mutants block in a coordinated fashion at intermediate stages. One smk1 mutant forms asci in which the four spores are surrounded only by prospore wall-like ...

Replication via sporulation is the replication strategy for all multicellular life, and may even be observed in unicellular life (such as with budding yeast). We consider diploid populations replicating via one of two possible sporulation mechanisms. (1) Asexual sporulation, whereby adult organisms produce single-celled diploid spores that grow into adults themselves. (2) Sexual sporulation, wh...