Two-component systems mediate bacterial signal transduction, employing a membrane sensor kinase and a cytoplasmic response regulator (RR). Environmental sensing is typically coupled to gene regulation. Understanding how input stimuli activate kinase autophosphorylation remains obscure. The EnvZ/OmpR system regulates expression of outer membrane proteins in response to osmotic stress. To identif...

Intrinsically disordered proteins (IDP) are a class of proteins that do not have a stable three-dimensional structure and can adopt a range of conformations playing various vital functional role. Alpha-synuclein is one such IDP which can aggregate into toxic protofibrils and has been associated largely with Parkinson's disease (PD) along with other neurodegenerative diseases. Osmolytes are smal...

Understanding the mechanism of protein fibrillization/aggregation and its prevention is the basis of development of therapeutic strategies for amyloidosis. An attempt has been made to understand the nature of interactions of osmolytes L-proline, 4-hydroxy-L-proline, sarcosine and trimethylamine N-oxide with the different stages of fibrillization of hen egg-white lysozyme by using a combination ...

Halophilic microbes living in hypersaline environments must counteract the detrimental effects of low water activity and salt interference. Some halophilic prokaryotes equilibrate their intracellular osmotic strength with the extracellular milieu by importing inorganic solutes, mainly potassium. These "salt-in" organisms characteristically have proteins that are highly enriched with acidic and ...

We report experimental and computational studies investigating the effects of three osmolytes, trimethylamine N-oxide (TMAO), betaine, and glycine, on the hydrophobic collapse of an elastin-like polypeptide (ELP). All three osmolytes stabilize collapsed conformations of the ELP and reduce the lower critical solution temperature (LSCT) linearly with osmolyte concentration. As expected from conve...

Peanut (Arachis hypogaea L.) and cotton (Gossypium hirsutum) plants were grown for 4 weeks in saline, isoosmotic rooting substrates with different proportions of K and Na. Isoosmotic media did not affect growth (except at the highest external K concentrations) or estimates of intracellular osmotic pressure in expanding leaves (i.e. osmotic pressure of leaf sap and intracellular osmotic pressure...

Madin-Darby canine kidney cells behave like the renal medulla and accumulate small organic solutes (osmolytes) in a hypertonic environment. The accumulation of osmolytes is primarily dependent on changes in gene expression of enzymes that synthesize osmolytes (sorbitol) or transporters that uptake them (myo-inositol, betaine, and taurine). The mechanism by which hypertonicity increases the tran...

Virtually all taxa use osmolytes to protect cells against biochemical stress. Osmolytes often occur in mixtures, such as the classical combination of urea with TMAO (trimethylamine N-oxide) in cartilaginous fish or the cocktail of at least six different osmolytes in the kidney. The concentration patterns of osmolyte mixtures found in vivo make it likely that synergy between them plays an import...

Background: Effects of cadmium (Cd) metal on growth, photosynthetic pigments, level of osmolytes and elements, and antioxidant potential of Brassica juncea seedlings were evaluated. Materials and Methods: Seeds were exposed to different concentrations of metal, i.e., 0, 0.2, 0.4, and 0.6 mM Cd. To investigate the metal influence on biochemical and physiological factors, observations were made o...

Osmolytes found endogenously in almost all living beings play an important role in regulating cell volume under harsh environment. Here, to address the longstanding questions about the underlying mechanism of osmolyte effects, we use femtosecond mid-IR pump-probe spectroscopy with two different IR probes that are the OD stretching mode of HDO and the azido stretching mode of azido-derivatized p...