Flavoenzyme dye-linked l-lactate dehydrogenase (Dye-LDH) is primarily involved in energy generation through electron transfer and exhibits potential utility in electrochemical devices. In this study, a gene encoding a Dye-LDH homolog was identified in a hyperthermophilic archaeon, Sulfurisphaera tokodaii. This gene was part of an operon that consisted of four genes that were tandemly arranged in the Sf. tokodaii genome in the following order: stk_16540, stk_16550 (dye-ldh homolog), stk_16560, and stk_16570. This gene cluster was expressed in an archaeal host, Sulfolobus acidocaldarius, and the produced enzyme was purified to homogeneity and characterized. The purified recombinant enzyme exhibited Dye-LDH activity and consisted of two different subunits (products of stk_16540 (α) and stk_16550 (β)), forming a heterohexameric structure (α3β3) with a molecular mass of approximately 253 kDa. Dye-LDH also exhibited excellent stability, retaining full activity upon incubation at 70 °C for 10 min and up to 80% activity after 30 min at 50 °C and pH 6.5–8.0. A quasi-direct electron transfer (DET)-type Dye-LDH was successfully developed by modification of the recombinant enzyme with an artificial redox mediator, phenazine ethosulfate, through amine groups on the enzyme’s surface. This study is the first report describing the development of a quasi-DET-type enzyme by using thermostable Dye-LDH. 相似文献
Sodium-glucose co-transporter 2 (SGLT2) inhibitors facilitate urine glucose excretion by reducing glucose reabsorption, leading to ameliorate glycemic control. While the main characteristics of type 2 diabetes mellitus are insufficient insulin secretion and insulin resistance, SGLT2 inhibitors have some favorable effects on pancreatic β-cell function and insulin sensitivity. SGLT2 inhibitors ameliorate fatty liver and reduce visceral fat mass. Furthermore, it has been noted that SGLT2 inhibitors have cardio-protective and renal protective effects in addition to their glucose-lowering effect. In addition, several kinds of SGLT2 inhibitors are used in patients with type 1 diabetes mellitus as an adjuvant therapy to insulin. Taken together, SGLT2 inhibitors have amazing multifaceted effects that are far beyond prediction like some emerging magical medicine. Thereby, SGLT2 inhibitors are very promising as relatively new anti-diabetic drugs and are being paid attention in various aspects. It is noted, however, that SGLT2 inhibitors have several side effects such as urinary tract infection or genital infection. In addition, we should bear in mind the possibility of diabetic ketoacidosis, especially when we use SGLT2 inhibitors in patients with poor insulin secretory capacity. 相似文献
Frontiers of Mechanical Engineering - Enabled by advancements in multi-material additive manufacturing, lightweight lattice structures consisting of networks of periodic unit cells have gained... 相似文献
In order to investigate the effective mechanism of pyrite catalyst, coal liquefaction was conducted using a 500 ml autoclave. When the chemical structure characteristics of products and product yields are considered as a whole, deoxygenation and dealkylation are found to be enhanced in the presence of pyrite catalyst. Further, it is surmised that depolymerization is faster than the removal of heteroatoms. 相似文献
By utilizing the fact that physical properties exclusive of elasticity of dilute polyacrylamide solutions do not change with elapsed time after preparation, the effect of elasticity on drag reduction and turbulent fluctuations in pipe flow was investigated experimentally. The oscillations of axial velocity and velocity gradient and the drag reduction in the laminar-turbulent transition region are affected significantly by the value of elasticity. The laminar-turbulent transition region moves to a higher Reynolds number as the value of elasticity increases. 相似文献
Polyamidethioethers were synthesized and evaluated as positive electron beam (EB) resists, The polyamidethioethers decomposed easily with EB exposure. At high doses (indicating low sensitivity), crosslinking reactions occurred for polyamidethioethers having C-S bonds produced by Michael addition, but the other polyamidethioethers did not crosslink. The C-S bonds produced by Michael addition may influence crosslinking rather than decomposition. The sensitivity of oxidized polyamidethioether was higher than that of the nonoxidized polymer with no change in resolution. The oxidized polyamidethioether had a high sensitivity and a high resolution, and is adaptable as a positive EB resist. 相似文献
There are many approaches to formulate multiple correspondence analysis of multi-item categorical data. A lower-rank approximation approach gives the freedom for the oblique rotation of axes. In the current paper, we apply the oblique rotation of axes to a variable-by-dimension matrix to arrive at simple structure. This matrix is defined in either of two different manners, that is, by treating categories as variables or, alternatively, by treating items as variables. For each of these two options, the standardized inner products between dimensions and variables are used as the elements of the component structure matrix. We adopt a promax method for the oblique rotation. In this method, scores are rotated in such a way that the above matrix is matched with the target matrix obtained from the result of the varimax rotation.
Turner’s combinator implementation (1979) of functional programs requires the memory space of size Ω(n2) in the worst case for translating given lambda expressions of lengthn to combinator graphs. In this paper a new idea named the BC-chain method for transferring actual arguments to variables is presented. We show that the BC-chain method requires onlyO(n) space for the translation. The basic idea is to group together into a single entity a sequence of combinatorsB, B′, C andC′, for a variable, which appear consecutively along a path in the combinator graph. We formulate two reduction algorithms in the new representation. The first algorithm naively simulates the original normal order reduction, while the second algorithm simulates it in constant time per unit operation of the original reduction. Another reduction method is also suggested, and a technique for practical implementation is briefly mentioned. 相似文献