Two-dimensional gels: An easy method for large quantities of proteins

A new two-dimensional gel technique has been developed that makes it possible to load large amounts of protein and still retain good resolution. Protein samples are added to the isoelectric-focusing acrylamide solution prior to polymerization. Focusing times are short, making it possible to complete both dimensions of a two-dimensional gel in five to six hours. The technique yields larger amounts of separated protein for sequencing, and also greatly increases the quality of two-dimensional immunoblots.     

An apparatus for sampling gut contents of large,living fishes

Synopsis Apparatus and methods are described and illustrated for flushing and retaining gut contents from large, living fishes with water supplied by a 12 volt portable pump.     

Rats' preferences for corn versus wood-based bedding and nesting materials

Corn by-products can be used as bedding and nesting products. Corn-cob bedding resists ammonia build-up and corn-husk nesting material resists dampness. It is not clear whether these advantages are at the expense of animal comfort. Corn cob was compared to aspen chip bedding, and corn husk to paper strip nesting material. Data from 20 rats with differential early bedding experience suggested that they prefer aspen chip, but are also biased towards the bedding they were raised on. Data from 10 rats with no prior nesting material experience suggested that paper strip was preferred over cornhusk. Thus, corn-cob products are not recommended except in situations where air quality and/or flooding are significant problems.     

A simple procedure for obtaining large quantities of tubulin subunits from newborn mouse brain

A simple, efficient two-step procedure of DEAE--Sephadex A--50 column chromatography followed by hydroxyapatite column chromatography for purification of alpha- and beta-tubulin subunits from newborn mouse brain is described. Stored frozen mouse brains can be used as a convenient starting material. Differential elution of alpha and beta subunits from hydroxyapatite was achieved using a linear gradient of 0.2--0.3 M phosphate buffer containing 2 M urea, 0.1% sodium dodecyl sulphate and 1 mM dithiothreitol. 20 mg of alpha-tubulin (purity: greater than 85%) and 16 mg of beta-tubulin (purity greater than 95%) completely separated from each other can be obtained in one experiment.     

A method for collecting large quantities of Cryptosporidium parasites

The intestinal mucoso may be regarded as a potential and abundant source of Cryptosporidium parvurn parasites from which all developmental stages might be collected. If intracellular stages could be recovered from the brush border, many of the limitations concerned with the use of oocysts and in vitro cultures may be overcome. Hans-Michael Muller, Lorella Ranucci, Edoordo Pozio and Andrea Crisonti discuss here how this can be done.     

An apparatus for the simultaneous casting of large numbers of uniform cylindrical polyacrylamide gels

An apparatus for the simultaneous casting of a large number of cylindrical polyacrylamide gels is described. Gels can be cast that are uniform with respect to length, loading-surface flatness, and internal polymerization properties. The basis of the method is casting the gels as an inverted single block which totally excludes oxygen from gel-loading surfaces during polymerization.     

Short Communication: Modification of a leaf-washing apparatus for the recovery of mites

Boller's funnel and sieve apparatus for extracting phytoseiid mites (Acari: Phytoseiidae) from leaves was modified. The modification consisted of including a reservoir dish enabling the placing of the whole sample of leaves into the apparatus, attaching a collecting chamber, simplification of the fixing of the fine lower sieve and adding an upper fine sieve. This modification enables the rapid processing of samples of up to 150 leaves.     

A high recovery method for concentrating microgram quantities of protein from large volumes of solution

A method is presented for the recovery of 40-80% of the protein from a 1 microgram/ml solution. The final protein pellet is free of detergent and other ionic compounds and is thus compatible with any denaturing solution. The primary structure of the protein is unaffected by the procedure, making the final pellet an ideal sample for any analytical procedure to determine protein structure.