Differential display polymerase chain reaction is technically challenging at a number of steps, including reliable reamplification of differentially expressed sequences after they are isolated from an acrylamide gel. As the only source of the sequence found to be of interest is the gel from which it was identified as being differentially expressed, failed attempts at reamplification can be part...

Protein engineering is a powerful tool for the improvement of the properties of biocatalysts. Previously we have applied protein engineering technologies to obtain an extremely stable variant of the thermolysin-like protease from Bacillus stearothermophilus [Van den Burg, Vriend, Veltman, Venema and Eijsink (1998) Proc. Natl. Acad. Sci. U.S.A. 95, 2056-2060]. This variant is much more resistant...

To understand specific ion effects on a molecular level we explore the effect of salts on the rotational mobility of a model amide using dielectric spectroscopy. Based on our previous studies on the effect of strong denaturing anions or cations, here we study the additivity of the anionic and cationic effect. Using salts consisting of denaturing spherical anions and spherical cations we find su...

A denaturing gradient gel electrophoresis (DGGE) assay was developed to rapidly discriminate species of avian Eimeria. Amplification by PCR of the small subunit ribosomal RNA gene (approximately 1,600 nucleotides) with Eimeria genus-specific primers followed by cloning and sequencing allowed us to carry out phylogenetic analyses and identify clone sequences to species level in most cases. Clone...

Base-catalyzed reversal of a psoralen-DNA cross-link has been observed under denaturing alkaline conditions at elevated temperatures. The cross-link was formed between 4'-(hydroxymethyl)-4,5',8-trimethylpsoralen and the two thymidine residues (T) on opposite strands of the double-stranded DNA formed from the self-complementary oligonucleotide 5'-GGGTACCC-3'. In contrast to the photoreversal of ...

and -IgM k and l light chains did not show the presence of monoclonal components. Reduction with mercaptoethanol (1:2 dilution), which dissociates complexes but does not dissociate albumin dimers, excluded the possible formation of complexes with a1-antitrypsin. Interferences by radio-opaque agents or medications, which could lead to the appearance in the CZE electropherograms of abnormal peaks...

We present an online tool (EquiBands, http://www.univie.ac.at/IECB/limno/equibands/EquiBands.html) that quantifies the matching of two bands considered to be the same in different samples, even when samples are applied to different denaturing gradient gel electrophoresis gels. With an environmental example we demonstrate the procedure for the classification of two bands of different samples wit...

Analysis of microbial communities associated with plants, insects and soil has been a significant challenge for plant protection researchers, because of the lack of techniques with which to access these populations. A new molecular community profiling technique, 16S rRNA gene-based PCR followed by denaturing gradient gel electrophoresis (DGGE), has been used to analyse microbial communities in ...

Three identical sequential batch reactors (SBRs) were each inoculated with sludge from a full-scale wastewater treatment plant (WWTP) treating a waste stream of different origin, i.e. a hospital, a meat processing company, and a municipal WWTP. The SBRs were run in parallel for 84 consecutive days to investigate whether the reactors would become more phylogenetically similar or stay separated c...

While there have been a vast number of studies on bacterial alpha diversity in the shallow terrestrial subsurface, beta diversity - how the bacterial community composition changes with spatial distance - has received surprisingly limited attention. Here, bacterial beta diversity and its controlling factors are investigated by denaturing gradient gel electrophoresis and cloning of samples from a...