Biological chemistry Hoppe-Seyler 

About: Biological chemistry Hoppe-Seyler is an academic journal. The journal publishes majorly in the area(s): Peptide sequence & Amino acid. It has an ISSN identifier of 0177-3593. Over the lifetime, 1544 publications have been published receiving 36315 citations.

Mechanisms of intracellular protein transport

Abstract: Recent advances have uncovered the general protein apparatus used by all eukaryotes for intracellular transport, including secretion and endocytosis, and for triggered exocytosis of hormones and neurotransmitters. Membranes are shaped into vesicles by cytoplasmic coats which then dissociate upon GTP hydrolysis. Both vesicles and their acceptor membranes carry targeting proteins which interact specifically to initiate docking. A general apparatus then assembles at the docking site and fuses the vesicle with its target.

Extensive Nitration of Protein Tyrosines in Human Atherosclerosis Detected by Immunohistochemistry

Abstract: Oxidation of lipoproteins is important for the initiation and propagation of the atherosclerotic lesion and may involve secondary oxidants derived from nitric oxide. Nitric oxide (NO) reacts at near diffusion limited rates with superoxide (O2-.) to form the strong oxidant, peroxynitrite (ONOO-). Nitration on the ortho position of tyrosine is a major product of peroxynitrite attack on proteins. Nitrotyrosine was detected in atherosclerotic lesions of formalin-fixed human coronary arteries with polyclonal and monoclonal antibodies. Binding was pronounced in and around foamy macrophages within the atheroma deposits. Nitration was also observed in early subintimal fatty streaks. Antibody binding was completely blocked by co-incubation with 10mM nitrotyrosine, but not by equivalent concentrations of aminotyrosine or phosphotyrosine. The presence of nitrotyrosine indicates that oxidants derived from nitric oxide such as peroxynitrite are generated in human atherosclerosis and may be involved in its pathogenesis.

Low concentrations of acid-soluble thiol (cysteine) in the blood plasma of HIV-1-infected patients.

Abstract: Blood plasma samples from HIV-1-infected persons contain elevated glutamate concentrations up to 6-fold the normal level and relatively low concentrations of acid-soluble thiol (i.e. decreased cysteine concentrations). The intracellular glutathione concentration in peripheral blood-mononuclear cells (PBMC) and monocytes from HIV antibody-positive persons are also significantly decreased. Therapy with azidothymidine (AZT) causes a substantial recovery of the plasma thiol levels; but glutamate levels remain significantly elevated and intracellular glutathione levels remain low. Cell culture experiments with approximately physiological amino-acid concentrations revealed that variations of the extracellular cysteine concentration have a strong influence on the intracellular glutathione level and the rate of DNA synthesis [( 3H]thymidine incorporation) in T cell clones and human and murine lymphocyte preparations even in the presence of several-fold higher cystine and methionine concentrations. Cysteine cannot be replaced by a corresponding increase of the extracellular cystine or methionine concentration. These experiments suggest strongly that the low cysteine concentration in the plasma of HIV-infected persons may play a role in the pathogenetic mechanism of the acquired immunodeficiency syndrome.

Cytokine regulation of matrix metalloproteinase activity and its regulatory dysfunction in disease.

Abstract: Matrix metalloproteinases (MMPs) represent a family of structurally and functionally related enzymes responsible for the proteolytic degradation of extracellular matrix (ECM) components such as basement membrane or interstitial stroma MMPs are important participants of normal tissue remodeling Due to their potential hazardous effects MMPs are highly regulated at different levels At the transcriptional level, MMP expression is precisely controlled by various cytokines acting through positive or negative regulatory elements of its genes Moreover, MMP activity is post-transcriptionally regulated by proteolytic activation of the latent proenzymes and by interaction with specific tissue inhibitors of metalloproteinases (TIMPs) Expression and secretion of both MMP activating enzymes and TIMPs are also influenced by cytokines Dysregulation of MMP production and activation may cause altered extracellular proteolysis that is associated with a number of diseases such as rheumatoid arthritis and tumor metastasis Thus, the molecular analysis of the regulatory mechanisms of gene expression and activity of MMPs and their inhibitors is essential for understanding the complex scenario of tissue remodeling and ECM degradation under both normal and pathological conditions

Human cathepsin O2, a novel cysteine protease highly expressed in osteoclastomas and ovary molecular cloning, sequencing and tissue distribution.

Abstract: A 1.6-kilobase full-length cDNA of a novel human cysteine protease has been isolated and sequenced. The nucleotide sequence encodes a polypeptide of 329 amino acids composed of a 15-residue N-terminal signal peptide, a 99-residue propeptide, and a mature protein of 215 amino acids. The deduced amino acid sequence contains two potential N-glycosylation sites, one located in the proregion and one in the mature enzyme. Comparison of the amino acid sequence of cathepsin O2 with that of known human lysosomal cysteine proteases revealed a substantial degree of similarity to cathepsins L and S. Northern blot analysis indicates predominant levels of expression in osteoclastomas and ovary and therefore the enzyme was named cathepsin O2. The extremely high expression levels of human cathepsin O2 in osteoclastomas suggest a major role of this novel enzyme in bone remodelling and bone related diseases.