Subject(s)
Biological Specimen Banks , Software , Data Curation , Humans , Quality Control , Specimen HandlingABSTRACT
PURPOSE: Carboxyterminally elongated and aminoterminally truncated Aß peptides as well as their pyroglutamate and oxidized derivates are major constituents of human amyloid plaques. The objective of the present study was to characterize aminoterminally truncated or oxidized Aß38, Aß40, and Aß42 peptide species in immunoprecipitated human cerebrospinal fluid (CSF). EXPERIMENTAL DESIGN: We invented a novel sequential aminoterminally and carboxyterminally specific immunoprecipitation protocol and used the Aß-SDS-PAGE/immunoblot for subsequent analysis of CSF Aß peptide patterns. RESULTS: In the present study, we identified the aminoterminally truncated Aß peptides 2-40 and 2-42 as well as oxidized forms of Aß1-38 and Aß1-42 in CSF. Our protocol allowed the quantification of a pattern of Aß peptides 1-38(ox), 2-40, and 2-42 in addition to the well known panel of Aß 1-37, 1-38, 1-39, 1-40, 1-40(ox), and 1-42 in a group of seven patients with peripheral polyneuropathy. CONCLUSIONS AND CLINICAL RELEVANCE: In the present approach, we could broaden the range of quantifiable Aß peptides described in previous studies (i.e., 1-37, 1-38, 1-39, 1-40, 1-40(ox), and 1-42) by Aß 1-38(ox), 2-40, and 2-42. An exact analysis of CSF Aß peptides regarding their carboxy- and aminoterminus as well as posttranslational modification seems promising with respect to diagnostic and pathogenic aspects.
Subject(s)
Amyloid beta-Peptides/cerebrospinal fluid , Immunoprecipitation/methods , Peptide Fragments/cerebrospinal fluid , Peripheral Nervous System Diseases/cerebrospinal fluid , Aged , Amyloid beta-Peptides/metabolism , Biomarkers/cerebrospinal fluid , Biomarkers/metabolism , Cross Reactions , Electrophoresis, Polyacrylamide Gel , Humans , Immunoblotting , Middle Aged , Oxidation-Reduction , Peptide Fragments/metabolism , Peripheral Nervous System Diseases/diagnosis , Peripheral Nervous System Diseases/metabolism , Peripheral Nervous System Diseases/pathology , Sensitivity and Specificity , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methodsABSTRACT
The first version of the Standard PREanalytical Code (SPREC) was developed in 2009 by the International Society for Biological and Environmental Repositories (ISBER) Biospecimen Science Working Group to facilitate documentation and communication of the most important preanalytical quality parameters of different types of biospecimens used for research. This same Working Group has now updated the SPREC to version 2.0, presented here, so that it contains more options to allow for recent technological developments. Existing elements have been fine tuned. An interface to the Biospecimen Reporting for Improved Study Quality (BRISQ) has been defined, and informatics solutions for SPREC implementation have been developed. A glossary with SPREC-related definitions has also been added.
Subject(s)
Biological Specimen Banks/standards , Biological Specimen Banks/organization & administration , Quality Control , Specimen Handling/standardsABSTRACT
Cupriavidus necator H16 (DSM 428), whose genome has been sequenced, was found to degrade N-acetyltaurine as a sole source of carbon and energy for growth. Utilization of the compound was quantitative. The degradative pathway involved an inducible N-acetyltaurine amidohydrolase (NaaS), which catalysed the cleavage of N-acetyltaurine to acetate and taurine. The degradation of the latter compound is via an inducible, degradative pathway that involves taurine dehydrogenase [EC 1.4.2.-], sulfoacetaldehyde acetyltransferase [EC 2.3.3.15], phosphotransacetylase [EC 2.4.1.8], a sulfite exporter [TC 9.A.29.2.1] and sulfite dehydrogenase [EC 1.8.2.1]. Induction of the expression of representative gene products, encoded by at least four gene clusters, was confirmed biochemically. The acetate released by NaaS was activated to acetyl-CoA by an inducible acetate-CoA ligase [EC 6.2.1.1]. NaaS was purified to homogeneity; it had a K(m) value of 9.4 mM for N-acetyltaurine, and it contained tightly bound Zn and Fe atoms. The denatured enzyme has a molecular mass of about 61 kDa (determined by SDS-PAGE) and the native enzyme was apparently monomeric. Peptide-mass fingerprinting identified the locus tag as H16_B0868 in a five-gene cluster, naaROPST (H16_B0865-H16_B0869). The cluster presumably encodes a LysR-type transcriptional regulator (NaaR), a membrane protein (NaaO), a soluteâ:âsodium symporter-family permease [TC 2.A.21] (NaaP), the metal-dependent amidohydrolase (NaaS) and a putative metallochaperone (COG0523) (NaaT). Reverse-transcription PCR indicated that naaOPST were inducibly transcribed.
