The desire to start evolution from scratch inside a computer memory is as old as computing. Here we demonstrate how viable computer programs can be established de novo in a Precambrian environment without supplying any specific instantiation, just starting with random bit sequences. These programs are not self-replicators, but act much more like catalysts. The microcontrollers used in the end a...

The occurrence of macromolecular change accompanying differentiation in embryonic or neoplastic development is well recognized, even if poorly understood.'+ In the course of immunochemical studies on macromolecular changes related to differentiation in the amphibian,".' we have had occasion to examine the antigenic composition of the f rog kidney and of the f rog renal adenocarcinoma, which is ...

Mast cells contain an enzyme which hydrolyzes 3-chloroacetoxy-2-naphthoic acid anilide. By using highly purified mast cells isolated by differential centrifugation in high density sucrose solutions we have been able to study this enzymatic activity in more detail. The enzyme has properties similar to those of chymotrypsin: Chymotrypsin will hydrolyze the histochemical substrate, and the chymotr...

The natural product-like 6,6″-biapigenin has been identified as only the second inhibitor of NEDD8-activating enzyme using virtual screening. This compound was active in enzyme and cell-based assays, with potency in the micromolar range.

Retinaldehyde dehydrogenases (RALDHs) convert retinal to retinoic acid, an important chordate morphogen. Retinal also occurs in some fungi, such as Fusarium and Ustilago spp., evidenced by the presence of rhodopsins and β-carotene cleaving, retinal-forming dioxygenases. Based on the assumption that retinoic acid may also be formed in fungi, we searched the Fusarium protein databases for RALDHs ...

Specific rabbit antisera against purified bovine pituitary carboxypeptidase processing enzyme (which has also been referred to as "enkephalin convertase") have been prepared and characterized. The antisera recognized both the purified soluble and the membrane-bound forms of the enzyme with equal affinity, suggesting that these two forms of the enzyme may possess many regions of structural homol...

BACKGROUND The polyamines putrescine, spermidine, and spermine are organic cations that are required for cell growth and differentiation. Ornithine decarboxylase (ODC), the first and rate-limiting enzyme in the polyamine biosynthetic pathway, is a highly regulated enzyme. METHODOLOGY AND RESULTS To use this enzyme as a potential drug target, the gene encoding putative ornithine decarboxylase ...

Due to variability of venom components from the same species of snakes that inhabit different regions, particular properties of the venom of Crotalus durissus terrificus that inhabits the North-East of Argentina were studied. Gyroxin, a thrombin-like enzyme, was isolated from this venom by gel filtration and affinity chromatography, it was found to be homogeneous according to SDS-PAGE, with a m...

Prodiginines, which are tripyrrole alkaloids displaying a wide array of bioactivities, occur as linear and cyclic congeners. Identification of an unclustered biosynthetic gene led to the discovery of the enzyme responsible for catalyzing the regiospecific C-H activation and cyclization of prodigiosin to cycloprodigiosin in Pseudoalteromonas rubra. This enzyme is related to alkylglycerol monooxy...

Gabonase, an enzyme which acts on fibrinogen and factor XI11 in uniquely thrombin-like ways, was purified to electrophoretic homogeneity from the venom of Bitis gabonica. On sodium dodecyl sulfate-polyacrylamide electrophoresis, the reduced protein behaved as a single chain with Mr = 30,600. The enzyme contains 20.6% carbohydrate, no free sulfhydryl groups and hence, from amino acid analysis, f...