Prothrombin is a vitamin K-dependent blood coagulation protein that undergoes posttranslational gamma-carboxylation and propeptide cleavage during biosynthesis. The propeptide contains the gamma-carboxylation recognition site that directs gamma-carboxylation. To identify the intracellular sites of carboxylation and propeptide cleavage, we monitored the synthesis of prothrombin in Chinese hamste...

the photosynthetic capacity of Siberian white birch and Japanese white birch (Betula platyphylla Sukatch. and B. platyphylla Sukatch. var. japonica Hara) were measured. Birch seedlings were raised with a CO2 partial pressure of 36 ± 0.3 Pa (i.e., ambient) or 70 ± 0.6 Pa at day/night temperatures of either 30/16 °C or 26/12 °C. Siberian birch leaves were smaller and thicker than Japanese birch l...

Studies presented here, with the criterion of the degree of binding of the biotin derivatives obtained from acetyl coenzyme A carboxylase to avidin, show that these compounds have an intact ureido ring, eliminating the diamine derivative as an intermediate in the carboxylation. With the use of carboxyl-14C-biotin acetyland propionyl-CoA carboxylases, it has been possible to show both in vivo an...

Carboxylation of aromatics by CO2 to generate corresponding carboxylic acids is recently providing a novel approach to utilize the green gas CO2, in which the activation of CO2 is the key procedure. Among the many catalytic systems employed in the carboxylation, the concept of “Frustrated Lewis Pairs” (FLPs) was scarcely mentioned, which perform excellently in activating small molecules like CO...

Studies presented here, with the criterion of the degree of binding of the biotin derivatives obtained from acetyl coenzyme A carboxylase to avidin, show that these compounds have an intact ureido ring, eliminating the diamine derivative as an intermediate in the carboxylation. With the use of carboxyl-14C-biotin acetyland propionyl-CoA carboxylases, it has been possible to show both in vivo an...

To identify the effect of nitrogen (N) nutrition on photosynthetic efficiency and mesophyll conductance of rice seedlings (Oryza sativa L., cv. 'Shanyou 63' hybrid indica China), hydroponic experiments with different concentrations of N were conducted in a greenhouse. Although leaf N concentration on a dry mass basis increased with increasing supply of N, no significant differences in seedling ...

In photosynthesis Rubisco catalyses the assimilation of CO(2) by the carboxylation of ribulose-1,5-bisphosphate. However, the catalytic properties of Rubisco are not optimal for current or projected environments and limit the efficiency of photosynthesis. Rubisco activity is highly regulated in response to short-term fluctuations in the environment, although such regulation may not be optimally...

Vitamin K contributes to bone health, probably through its role as cofactor in the carboxylation of osteocalcin. Intervention studies in adults have demonstrated that markedly higher osteocalcin carboxylation is obtained by intakes of vitamin K well above the current recommended dietary intake. However, the relationship between increased vitamin K2 intake and enhanced osteocalcin carboxylation ...

The metabolism of acetone was investigated in the actinomycete Rhodococcus rhodochrous (formerly Nocardia corallina) B276. Suspensions of acetone- and isopropanol-grown R. rhodochrous readily metabolized acetone. In contrast, R. rhodochrous cells cultured with glucose as the carbon source lacked the ability to metabolize acetone at the onset of the assay but gained the ability to do so in a tim...