PubMed · 4956586
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
F Milgrom, U Loza. 1966. Complement-mediated hemolysis in agar gel.. https://pubmed.ncbi.nlm.nih.gov/4956586/
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Alkane solubilities were measured experimentally for high-density biomass. The resulting Henry's law constants for propane were found to decrease significantly for both dense yeast suspensions and an actual propane-degrading biofilm consortium. At the biomass densities of a typical biofilm, propane solubility was about an order of magnitude greater than that in pure water. For example, a dense biofilm had a propane Henry's law constant of 0.09+/-0.04 atm m(3) mol(-1) compared to 0.6+/-0.1 atm m(3) mol(-1) measured in pure water. The results were modeled with mixing rules and compared with octanol-water mixtures. Hydrogels (agar) and salts decreased the alkane solubility. By considering a theoretical solubility of propane in dry biomass, estimates were made of intrinsic Henry's law constants for propane in pure yeast and biomass, which were 13+/-2 and 5+/-2 atm kg biomass mol(-1) for yeast and biofilm consortium, respectively.
Xylose lysine decarboxylase (XLD) medium, a selective plating medium, can inhibit heat-injured Salmonella typhimurium from growing, whereas tryptic soy agar (TSA), a nonselective medium, does not. To facilitate recovery of heat-injured S. typhimurium cells while providing selectivity of isolation of S. typhimurium from other bacteria in the sample, a thin agar layer (TAL) procedure was developed by overlaying 14 ml of nonselective medium (TSA) onto prepoured and solidified XLD medium in a 8.5 cm diameter Petri dish. During the first few hours of incubating the plate, the injured S. typhimurium repaired and started to grow in the TSA. During the resuscitation of injured cells, the selective agents from XLD were diffused to the TSA top layer part. Once the selective agents diffused to the top part of the TAL, the resuscitated S. typhimurium started to produce a typical reaction (black color) and other microorganisms were inhibited by the selective agents. The recovery rate for heat-injured (55 degrees C for 15 min) S. typhimurium with the TAL method was compared with TSA, XLD, and the traditional overlay method (OV; pouring selective agar on top of resuscitated cells on TSA agar 3-4 h after incubation). No significant difference occurred among TSA, OV, and TAL (P > 0.05) for enumeration of heat-injured S. typhimurium, but they recovered significantly higher numbers than from XLD agar (P < 0.05).
The actin cytoskeleton is implicated in many cellular processes, such as cell adhesion, locomotion, contraction and cytokinesis, which are central to any development. The extent of polymerization, cross-linking, and bundling of actin is regulated by several actin-binding proteins. Knock-out mutations in these proteins have revealed in many cases only subtle, if any, defects in development, suggesting that the actin system is redundant, with multiple proteins sharing overlapping functions. The apparent redundancy may, however, reflect limitations of available laboratory assays in assessing the developmental role of a given protein. By using a novel assay, which reproduces conditions closer to the natural ones, we have re-examined the effects of disruption of many actin-binding proteins, and show here that deletion of alpha-actinin, interaptin, synexin, 34-kDa actin-bundling protein, and gelation factor affect to varying degrees the efficiency of Dictyostelium cells to complete development and form viable spores. No phenotypic defects were found in hisactophilin or comitin null mutants.