Rhenium complexes enzymes

The present volume is the fourth in the series and covers the topics lithium in biology, the structure and function of ceruloplasmin, rhenium complexes in nuclear medicine, the anti-HIV activity of macrocyclic polyamines and their metal complexes, platinum anticancer dmgs, and functional model complexes for dinuclear phosphoesterase enzymes. The production of this volume has been overshadowed by a very sad event—the passing away of the senior editor, Professor Robert W. Hay. It was he who conceived the idea of producing this series and who more than anyone else has been responsible for its continuation. A tribute by one of his many friends, Dr. David Richens, is included in this Volume. 

Rapid development of this area followed the discovery of routes to these complexes, either by ready conversion of terminal alkynes to vinylidene complexes in reactions with manganese, rhenium, and the iron-group metal complexes (11-14) or by protonation or alkylation of some metal Recent work has demonstrated the importance of vinylidene complexes in the metabolism of some chlorinated hydrocarbons (DDT) using iron porphyrin-based enzymes (15). Interconversions of alkyne and vinylidene ligands occur readily on multimetal centers. Several reactions involving organometallic reagents may proceed via intermediate vinylidene complexes. 

Cat B is an abundant and ubiquitously expressed cysteine peptidase of the papain family and makes up a major fraction of lysosomal enzymes that is capable of degrading components of the extracellular matrix in various diseases [30-32]. Cat B is also a prognostic marker for several types of cancer [33], and increased expression and secretion of cat B has been shown to be involved in the migration and invasion of various tumours [34—36], The precise role of cat B in solid tumours is not fully understood, but it has been proposed to participate, along with other cysteine cathepsins, in metastasis, angiogenesis, and tumour progression [37], Indeed, cat B inhibitors reduce both tumour cell motility and invasiveness in vitro [38], Recently, metal complexes based on rhenium, gold and palladium were shown to be effective inhibitors of cat B [39-44],... 

Many reported photocatalysts are constmcted with both a photosensitizer, which initiates photochemical one-electron transfer, and a catalyst which converts one-electron transfer to multi-electron reduction of CO2. As the photosensitizer component, metal complexes, organic compounds, and semiconductors have been used. These have been combined with various catalysts, such as metal complexes, metal particles, and enzymes. Some exceptional photocatalysts can fill both roles, such as rhenium(l) complexes (see Sect. 2.1.1) and Ti02 (Sect. 3.2). 

X 10" M n= ) and 5-hydroxyindole-3-acetic acid (Ka = 2.0x 10" M = 1). The rhenium(I) indole complexes can inhibit another indole-binding protein, tryptophanase. A standard assay, which is on the basis of the conversion of L-serine to pyruvate by the enzyme, has been carried out. Under the standard experimental conditions, at [L-serine] = 800 mM, free indole inhibit 53% of the enzyme activity, while the indole-containing complexes... 

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