PMID: 9531047Apr 8, 1998Paper

Enhancement of fibrinolysis by plactins: structure-activity relationship and effects in human U937 cells and in mice

Thrombosis and Haemostasis
T InoueA Endo

Abstract

Plactin D, a cyclic pentapeptide [cyclo(-D-Val-L-Leu-D-Leu-L-Phe-D-Arg-)] produced by a fungal strain, enhances fibrinolytic activity (6). The present study deals with the structure-activity relationship of plactins and their effects in U937 cells and mice. The results obtained from 50 plactin D analogues with a single amino acid substitution demonstrated that the following substitutions were detrimental: the enantiomer for each of the five residues; a polar, an acidic or a basic residue for D-Val, L-Leu, D-Leu or L-Phe; a polar, a hydrophobic or an acidic residue for D-Arg. On the other hand, a compound with L-Leu or L-Val in place of L-Phe was seven times as active as plactin D. These results suggest an essential role of a sterically restricted arrangement of four hydrophobic residues and the adjacent basic residue. The enhancement of fibrinolysis was dependent on plasma, ranging from 2- to 3-fold when U937 cells were incubated with 15-30 microM plactin D in the presence of 6-50% plasma, while no elevation was observed when cells were incubated in the absence of plasma. Plasminogen alone could not substitute for plasma. The plactin D effect was totally abolished by anti-urokinase IgG but not by anti-tissue plasminogen activat...Continue Reading

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.