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Recently, with the vigorous development of the Internet of Things (IoT) technology, all kinds of intelligent home appliances in the market are constantly innovating. The public requirements for residential safety and convenience are also increasing. Meanwhile, with the improvement of indigenous medical technology and quality of life, people's average lifespan is gradually increasing. However, countries around the world are facing the problem of aging societies. Hand gesture recognition is gaining popularity in the fields of gesture control, robotics, or medical applications. Therefore, how to create a convenient and smart control system of home appliances for the elderly or the disabled has become the objective of this study. It aims to use Google MediaPipe to develop a hand tracking system, which detected 21 key points of a hand through the camera lens of a mobile device and used a vector formula to calculate the angle of the intersection of two lines based on four key points. After the angle of bending finger is obtained, users' hand gesture can be recognized. Our experiments have confirmed that the recognition precision and recall values of hand gesture for numbers 0–9 reached 98.80% and 97.67%, respectively; and the recognition results were used to control home appliances through the low-cost IoT-Enabled system. [ABSTRACT FROM AUTHOR]

Octaprenyl pyrophosphate synthase (OPPs), which belongs to the E-type prenyltransferase family, catalyses the successive condensation of farnesyl pyrophosphate with five isopentenyl pyrophosphate molecules to form trans-C40-octaprenyl pyrophosphate (OPP). OPP is essential for the biosynthesis of bacterial ubiquinone or menaquinone side chains, which play an important role in the electron-transport system. Here, Escherichia coli OPPs was expressed, purified and crystallized. The crystals, which belonged to the orthorhombic space group P21212, with unit-cell parameters a = 117.0, b = 128.4, c = 46.4 Å, were obtained by the sitting-drop vapour-diffusion method and diffracted to 2.2 Å resolution. Initial phase determination by molecular replacement (MR) clearly indicated that the crystal contained one homodimer per asymmetric unit. Further model building and structural refinement are in progress. [ABSTRACT FROM AUTHOR]

The endoglucanase EglA from Piromyces rhizinflata found in cattle stomach belongs to the GH5 family of glycoside hydrolases. The crystal structure of the catalytic domain of EglA shows the (β/α)8-barrel fold typical of GH5 enzymes. Adjacent to the active site of EglA, a loop containing a disulfide bond not found in other similar structures may participate in substrate binding. Because the active site was blocked by the N-terminal His tag of a neighbouring protein molecule in the crystal, enzyme-substrate complexes could not be obtained by soaking but were prepared by cocrystallization. The E154A mutant structure with a cellotriose bound to the −3, −2 and −1 subsites shows an extensive hydrogen-bonding network between the enzyme and the substrate, along with a stacking interaction between Trp44 and the −3 sugar. A possible dimer was observed in the crystal structure, but retention of activity in the E242A mutant suggested that the enzyme probably does not function as a dimer in solution. On the other hand, the first 100 amino acids encoded by the original cDNA fragment are very similar to those in the last third of the (β/α)8-barrel fold, indicating that EglA comprises at least two catalytic domains acting in tandem. [ABSTRACT FROM AUTHOR]

S-Adenosylhomocysteine hydrolase (SAHH) catalyzes the reversible conversion of S-adenosylhomocysteine into adenosine and homocysteine. The SAHH from Thermotoga maritima ( TmSAHH) was expressed in Escherichia coli and the recombinant protein was purified and crystallized. TmSAHH crystals belonging to space group C2, with unit-cell parameters a = 106.3, b = 112.0, c = 164.9 Å, β = 103.5°, were obtained by the sitting-drop vapour-diffusion method and diffracted to 2.85 Å resolution. Initial phase determination by molecular replacement clearly indicated that the crystal contains one homotetramer per asymmetric unit. Further refinement of the crystal structure is in progress. [ABSTRACT FROM AUTHOR]

Objectives Methods Results Interpretations Hereditary transthyretin (TTR) amyloidosis (ATTRv) is frequently complicated by polyneuropathy (ATTRv‐PN) and cardiomyopathy (ATTRv‐CM). The long‐term efficacy of diflunisal on both polyneuropathy and cardiomyopathy in ATTRv patients, especially those with non‐V30M genotypes, has not been fully investigated and compared with that of tafamidis.We compared the structural and biochemical characteristics of A97S‐TTR complexed with tafamidis with those of diflunisal, and prospectively followed up and compared the progression of polyneuropathy and cardiomyopathy between ATTRv‐PN patients taking diflunisal and those taking tafamidis.Both diflunisal and tafamidis effectively bind to the two thyroxine‐binding sites at the A97S‐TTR dimer–dimer interface and equally and almost sufficiently reduce amyloid fibril formation. Thirty‐five ATTRv‐PN patients receiving diflunisal and 22 patients receiving tafamidis were enrolled. Compared with no treatment, diflunisal treatment significantly delayed the transition of FAP Stage 1 to 2 and Stage 2 to 3 and decreased the deterioration in parameters of the ulnar nerve conduction study (NCS). The progression of FAP stage or NCS parameters did not differ between patients treated with diflunisal and those treated with tafamidis. Both diflunisal and tafamidis treatments significantly decreased radiotracer uptake on 99mTc‐PYP SPECT and stabilized cardiac wall thickness and blood pro‐B‐type natriuretic peptide levels. No significant adverse events occurred during diflunisal or tafamidis treatment.The binding patterns of both tafamidis and diflunisal to A97S‐TTR closely resembled those observed in the wild type. Diflunisal can effectively delay the progression of polyneuropathy and cardiomyopathy with similar efficacy to tafamidis and may become a cost‐effective alternative treatment for late‐onset ATTRv‐PN. [ABSTRACT FROM AUTHOR]

β-1,3-1,4-Glucanases catalyze the specific hydrolysis of internal β-1,4-glycosidic bonds adjacent to the 3- O-substituted glucose residues in mixed-linked β-glucans. The thermophilic glycoside hydrolase CtGlu16A from Clostridium thermocellum exhibits superior thermal profiles, high specific activity and broad pH adaptability. Here, the catalytic domain of CtGlu16A was expressed in Escherichia coli, purified and crystallized in the trigonal space group P3121, with unit-cell parameters a = b = 74.5, c = 182.9 Å, by the sitting-drop vapour-diffusion method and diffracted to 1.95 Å resolution. The crystal contains two protein molecules in an asymmetric unit. Further structural determination and refinement are in progress. [ABSTRACT FROM AUTHOR]

The NADH-dependent ( R)-carbonyl reductase from Candida parapsilosis (RCR) catalyzes the asymmetric reduction of 2-hydroxyacetophenone (HAP) to produce ( R)-1-phenyl-1,2-ethanediol [( R)-PED], which is used as a versatile building block for the synthesis of pharmaceuticals and fine chemicals. To gain insight into the catalytic mechanism, the structures of complexes of RCR with ligands, including the coenzyme, are important. Here, the recombinant RCR protein was expressed and purified in Escherichia coli and was crystallized in the presence of NAD+. The crystals, which belonged to the orthorhombic space group P212121, with unit-cell parameters a = 85.64, b = 106.11, c = 145.55 Å, were obtained by the sitting-drop vapour-diffusion method and diffracted to 2.15 Å resolution. Initial model building indicates that RCR forms a homotetramer, consistent with previous reports of medium-chain-type alcohol dehydrogenases. [ABSTRACT FROM AUTHOR]

The β-L-arabinofuranosidase (HypBA1) from Bifidobacterium longum JCM 1217 hydrolyzes the β-1,2-linked arabinofuranose disaccharide to release L-arabinoses. HypBA1 was classified into glycoside hydrolase family 127 (GH127) by the CAZy website (). The enzyme was expressed in Escherichia coli and the purified recombinant protein was crystallized. Crystals belonging to the primitive hexagonal space group P3 x21, with unit-cell parameters a = b = 75.9, c = 254.0 Å, were obtained by the sitting-drop vapour-diffusion method and diffracted to 2.78 Å resolution. A BLASTP search () of the Protein Data Bank did not reveal any similar crystal structures. Structural determination by using SeMet MAD and MIR methods is in progress. [ABSTRACT FROM AUTHOR]

CC-type chemokine ligand 5 (CCL5) has been known to regulate immune responses by mediating the chemotaxis of leukocytes. Depending on the environment, CCL5 forms different orders of oligomers to interact with targets and create functional diversity. A recent CCL5 trimer structure revealed that the N-terminal conversed F12-A13-Y14 ( 12 FAY 14 ) sequence is involved in CCL5 aggregation. The CCL5- 12 AAA 14 mutant with two mutations had a deficiency in the formation of high-order oligomers. In the study, we clarify the respective roles of F12 and Y14 through NMR analysis and structural determination of the CCL5- 12 AAA 14 mutant where F12 is involved in the dimer assembly and Y14 is involved in aggregation. The CCL5- 12 AAA 14 structure contains a unique dimer packing. The backbone pairing shifts for one-residue in the N-terminal interface, when compared to the native CCL5 dimer. This difference creates a new structural orientation and leads to the conclusion that F12 confines the native CCL5 dimer configuration. Without F12 anchoring in the position, the interfacial backbone pairing is permitted to slide. Structural plasticity occurs in the N-terminal interaction. This is the first case to report this structural rearrangement through mutagenesis. The study provides a new idea for chemokine engineering and complements the understanding of CCL5 oligomerization and the role of the 12 FAY 14 sequence.

Xylanase, which catalyzes the random hydrolysis of internal xylosidic linkages, is a critical enzyme participating in xylan decomposition and has been widely applied in industrial utilizations. Xylanase isolated from the extremophilic Streptomyces sp. S9 (XynAS9) possesses broad adaptability to temperature and pH and thus is an attractive candidate in industrial applications. In particular, the major products of XynAS9 are xylose and xylobiose, which enable the subsequent bioconversion to be carried out with higher efficiency. Therefore, the three-dimensional structure of XynAS9 and its catalytic machinery are of great interest. Here, recombinant XynAS9 protein was expressed in Pichia pastoris, purified and crystallized. Crystals belonging to the hexagonal space group P6(5)22, with unit-cell parameters a = b = 80.9, c = 289.3 Å, were obtained by the sitting-drop vapour-diffusion method and diffracted to 2.08 Å resolution. Initial phase determination using molecular replacement indicated that the crystal contains one molecule in an asymmetric unit. Further model building and structural refinement are in progress.

β-1,4-Mannanase (β-mannanase) is a key enzyme in decomposing mannans, which are abundant components of hemicelluloses in the plant cell wall. Therefore, mannan hydrolysis is highly valuable in a wide array of industrial applications. β-Mannanase isolated from Aspergillus niger BK01 (ManBK) was classified into glycoside hydrolase family GH5. ManBK holds great potential in biotechnological applications owing to its high thermostability. Here, ManBK was expressed and purified in Pichia pastoris and the recombinant protein was crystallized. Crystals belonging to the orthorhombic space group C222₁, with unit-cell parameters a=93.58, b=97.05, c=147.84 Å, were obtained by the sitting-drop vapour-diffusion method and diffracted to 1.57 Å resolution. Structure determination using molecular-replacement methods is in progress.