A double mutant of the single-domain protein barstar having a single tryptophan (W53) was made by mutating the remaining two tryptophans (W38 and W44) into phenylalanines. W53 is buried in the core of barstar. Time-resolved fluorescence of the mutant barstar (W38FW44F) showed that W53 has a single fluorescence lifetime in the native (N) state and has three lifetimes in the molten globule-like l...

Streblin, a serine proteinase from plant Streblus asper, has been used to investigate the conformational changes induced by pH, temperature, and chaotropes. The near/far UV circular dichroism activities under fluorescence emission spectroscopy and 8-aniline-1-naphthalene sulfonate (ANS) binding have been carried out to understand the unfolding of the protein in the presence of denaturants. Spec...

We have developed a simple protocol for isolating RNA from both cell culture and tissue from human and animal sources, using guanidine thiocyanate and guanidine hydrochloride, but no organic solvents. The protocol reproducibly yielded 15 to 25 micrograms of high-quality RNA per 10(6) cells of human and animal origin and 1 to 1.1 mg of RNA per gram of human placental tissue. The RNA so obtained ...

Attempts have been made to explain the action of certain proteindenaturing agents, such as organic solvents, urea, guanidine halides, and salicylates, in terms of (a) physical solvent effects (cf. (4)) or (b) unspecified intermediary combination between denaturant and protein (cf. (5)). Recent work has shown that the denaturing effect of guanidine hydrochloride, one of the most powerful denatur...

In this study, membranes were prepared from hydrophilic cellulose acetate (CA) and antibacterial polyhexamethylene guanidine hydrochloride (PHMG) by phase inversion method to improve membrane separation antifouling capacities. The influence of preparation conditions on structure performance has been investigated evaluated. experimental results indicated that the CA have an asymmetric with a den...

A mesoporous g-C3N4 with guanidine hydrochloride as precursor was prepared by molten salt assisted hard template of silica (SiO2) aerogel for photocatalytic degradation tetracycline (TC). The study shows that the successfully synthesized presented a coral-like rod shaped and heptazine ring structure. When amount SiO2 1.4 g, lower band gap (2.31 eV) sample (GM-1.4) interfacial resistance display...

Sessile marine sponges provide an abundance of unique and diversified scaffolds. In particular, marine guanidine alkaloids display a very wide range of biological applications. A large number of cyclic guanidine alkaloids, including crambines, crambescins, crambescidins, batzelladines or netamins have been isolated from Poecilosclerida marine sponges. In this review, we will explore the chemodi...

Guanidine applied to Nitella may lower the threshold of E.M.F. required to produce electrical stimulation and may give rise to trains of action currents. Its effect thus appears to be somewhat similar to that observed in animals. Rapid action currents are produced as well as "square topped" action curves and transitional forms. These effects may be due in part to increased protoplasmic conducti...

A simple and Noval Synthesis of guanidine derivatives is presented in this study. The construction of the Central basic Scaffolds is achieved by the using of HgCl2 as a promoter. The Formation of product of substituted guanidines controlled by amount of reactant. Further a new fast-tract access to N-1(Boc)-N-(2) cyclohexyl-N(3) phenyl-guanidine was developed.

Due to their remarkably high structural stability, proteins from extremophiles are particularly useful in numerous biological applications. Their utility as alternative protein scaffolds could be especially valuable in small antibody mimetic engineering. These artificial binding proteins occupy a specific niche between antibodies and low molecular weight substances, paving the way for developme...