Torrey Pines Institute for Molecular Studies

About: Torrey Pines Institute for Molecular Studies is a nonprofit organization based out in San Diego, California, United States. It is known for research contribution in the topics: T cell & Antigen. The organization has 2323 authors who have published 2217 publications receiving 112618 citations.

Determination of the secondary structure of selected melittin analogues with different haemolytic activities

Abstract: In earlier studies, we have reported that minor modifications in the amino acid sequence of melittin result in dramatic changes in its biological activity. In the current study, we have investigated the secondary structure of melittin analogues with either increased or decreased haemolytic activity in order to further our understanding of the structural features involved in the binding and/or insertion of peptides into a phospholipid membrane from solution. This was accomplished by analysing the c.d. spectra of the analogues in solutions of various ionic strength and, separately, in the presence of micelles. These studies permit the assessment of the effect of small sequence modifications (i.e. single amino acid omission or substitution) on the self-association-induced secondary structure of melittin in aqueous solution, as well as its binding affinity to micelles. It was found that amphipathicity, as well as interchain distances and the orientation of hydrophobic residues, were involved in the induction of stabilized structures.

Stopped-flow kinetic analysis of long-chain fatty acid dissociation from bovine serum albumin.

Abstract: The kinetics of the interaction of long-chain fatty acids (referred to as fatty acids) with albumin is critical to understanding the role of albumin in fatty acid transport. In this study we have determined the kinetics of fatty acid dissociation from BSA and the BSA-related fatty acid probe BSA-HCA (BSA labelled with 7-hydroxycoumarin-4-acetic acid) by stopped-flow methods. Fatty acid-albumin complexes of a range of natural fatty acid types and albumin molecules (donors) were mixed with three fatty acid-binding acceptor proteins. Dissociation of fatty acids from the donor was monitored by either the time course of donor fluorescence/absorbance or the time course of acceptor fluorescence. The results of these measurements indicate that fatty acid dissociation from BSA as well as BSA-HCA is well described by a single exponential function over the entire range of fatty acid/albumin molar ratios used in these measurements, from 0.5:1 to 6:1. The observed rate constants (k(obs)) for the dissociation of each fatty acid type reveal little or no dependence on the initial fatty acid/albumin ratio. However, dissociation rates were dependent upon the type of fatty acid. In the case of native BSA with an initial fatty acid/BSA molar ratio of 3:1, the order of k(obs) values was stearic acid (1.5 s(-1)) < oleic acid < palmitic acid congruent with linoleic acid

Normalization and binning of historical and multi‐source microsatellite data: overcoming the problems of allele size shift with allelogram

Abstract: Microsatellite allele data have long been plagued by size shifts that can at best make it difficult to accurately assign genotypes to allele products, and at worse can cause whole batches of data from different instruments, dates or laboratories to be incorrectly assigned. Although modern genotyping technology (capillary electrophoresis) has overcome many of these problems, concern remains regarding the consistency of scores within a laboratory over time and between laboratories when combining data from multiple sources into a single analysis. There remain a large number of laboratories using older technologies or combining data from multiple sources. In addition, thousands of data sets that could potentially be expanded as samples become available are generally regarded as unusable because of the effort that would be required to validate congruence of genotypes from old and new data sets. We present methods to normalize and bin alleles from multiple data sources using a relatively small set of controls and the freely available program allelogram.