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The YggS/PLPBP protein (also called COG0325 or PLPHP) is a conserved pyridoxal 5ʹ-phosphate (PLP)-binding protein present in all 3 domains of life. Recent studies have demonstrated that disruption or mutation of this protein has multifaceted effects in various organisms, including vitamin B6-dependent epilepsy in humans. In Escherichia coli, disruption of this protein—encoded by yggS—perturbs Thr-Ile/Val metabolism, one-carbon metabolism, coenzyme A synthesis, and vitamin B6 homeostasis. This protein is critical for maintaining low levels of pyridoxine 5ʹ-phosphate (PNP) in various organisms. In the yggS-deficient E. coli strain, inhibition of PLP-dependent enzymes, such as the glycine cleavage system by PNP, is the root cause of metabolic perturbation. Our data suggest that the YggS/PLPBP protein may be involved in the balancing of B6 vitamers by mediating efficient turnover of protein-bound B6 vitamers. This paper reviews recent findings on the function of the YggS/PLPBP protein.

The pupae of lepidopterans contain high concentrations of endogenous d-serine. In the silkworm Bombyx mori, d-serine is negligible during the larval stage but increases markedly during the pupal stage, reaching 50% of the total free serine. However, the physiological function of d-serine and the enzyme responsible for its production is unknown. Herein, we identified a new type of pyridoxal 5′-phosphate (PLP)-dependent serine racemase (SR) that catalyses the racemization of l-serine to d-serine in B. mori. This silkworm SR (BmSR) has an N-terminal PLP-binding domain that is homologous to mammalian SR and a C-terminal putative ligand-binding regulatory-like domain (ACT-like domain) that is absent in mammalian SR. Similar to mammalian SRs, BmSR catalyses the racemization and dehydration of both serine isomers. However, BmSR is different from mammalian SRs as evidenced by its insensitivity to Mg2+/Ca2+ and Mg-ATP—which are required for activation of mammalian SRs—and high d-serine dehydration activity. At the pupal stage, the SR activity was predominantly detected in the fat body, which was consistent with the timing and localization of BmSR expression. The results are an important first step in elucidating the physiological significance of d-serine in lepidopterans.

cis-Prenyltransferases (cPTs) form linear polyprenyl pyrophosphates, the precursors of polyprenyl or dolichyl phosphates that are essential for cell function in all living organisms. Polyprenyl phosphate serves as a sugar carrier for peptidoglycan cell wall synthesis in bacteria, a role that dolichyl phosphate performs analogously for protein glycosylation in eukaryotes and archaea. Bacterial cPTs are characterized by their homodimeric structure, while cPTs from eukaryotes usually require two distantly homologous subunits for enzymatic activity. This study identifies the subunits of heteromeric cPT, Af1219 and Af0707, from a thermophilic sulphur-reducing archaeon, Archaeoglobus fulgidus. Both subunits are indispensable for cPT activity, and their protein–protein interactions were demonstrated by a pulldown assay. Gel filtration chromatography and chemical cross-linking experiments suggest that Af1219 and Af0707 likely form a heterotetramer complex. Although this expected subunit composition agrees with a reported heterotetrameric structure of human hCIT/NgBR cPT complex, the similarity of the quaternary structures is likely a result of convergent evolution.

d-Aspartate is found in the nervous and reproductive system and participates in various physiological roles. While several lines of evidence suggest that this amino acid has an endogenous origin, the enzyme responsible for mammalian d-Asp biosynthesis has not yet been identified. We show that mammalian serine racemase (SRR), the primary enzyme responsible for brain d-Ser production, catalyses Asp racemization via a two-base mechanism. We observed that overexpression of SRR in rat pheochromocytoma PC12 cells resulted in an increase in intracellular d-Asp compared with control cells, demonstrating that SRR functions as an Asp racemase in the cells. To investigate the impact of endogenous SRR on endogenous d-Asp levels in the cells, we generated SRR-knockout (SRR-KO) PC12 cells. The SRR-KO cells exhibited decreased intracellular d-Ser levels, but production levels of d-Asp were unaffected. In contrast, SRR-KO mice showed significantly decreased d-Asp levels in their frontal cortices and hippocampi, where SRR is normally highly expressed, while d-Asp levels in the cerebellum and testes remained unchanged. Our results indicate that SRR indeed acts as a d-Asp biosynthetic enzyme in some organs and/or tissues, and also provide evidences that there should be some additional enzyme for d-Asp synthesis in mammals.

Bacillus subtilis GabR is a transcriptional regulator consisting of a helix-turn-helix N-terminal DNA-binding domain, a pyridoxal 5'-phosphate (PLP)-binding C-terminal domain that has a structure homologous to aminotransferases, and a linker of 29 amino acid residues. In the presence of γ-aminobutyrate (GABA), GabR activates the transcription of gabT and gabD, which encode GABA aminotransferase and succinate semialdehyde dehydrogenase, respectively. We expressed N-terminal and C-terminal domain fragments (named N'-GabR and C'-GabR) in Escherichia coli cells, and obtained N'-GabR as a soluble monomer and C'-GabR as a soluble dimer. Spectroscopic studies suggested that C'-GabR contains PLP and binds to d-Ala, β-Ala, d-Asn and d-Gln, as well as GABA, although the intact GabR binds only to GABA. N'-GabR does not bind to the DNA fragment containing the GabR-binding sequence regardless of the presence or absence of C'-GabR. A fusion protein consisting of N'-GabR and 2-aminoadipate aminotransferase of Thermus thermophilus bound to the DNA fragment. These results suggested that each domain of GabR could be an independent folding unit. The C-terminal domain provides the N-terminal domain with DNA-binding ability via dimerization. The N-terminal domain controls the ligand specificity of the C-terminal domain. Connection by the linker is indispensable for the mutual interaction of the domains.

(E)-4-hydroxy-3-methylbut-2-en-1-yl diphosphate (HMBPP) is an intermediate of the methylerythritol phosphate pathway. Utilization of HMBPP by lycopene elongase from Corynebacterium glutamicum, which is a UbiA-family prenyltransferase responsible for C50 carotenoid biosynthesis, was investigated using an Escherichia coli strain that contained the exogenous mevalonate pathway as well as the carotenoid biosynthetic pathway. Inhibition of the endogenous methylerythritol phosphate pathway resulted in loss of the production of C50 carotenoid flavuxanthin, while C40 lycopene formation was retained. Overexpression of E. coli ispH gene, which encodes HMBPP reductase, also decreased the production of flavuxanthin in E. coli cells. These results indicate the preference of lycopene elongase for HMBPP instead of the previously proposed substrate, dimethylallyl diphosphate. Furthermore, several (all-E)-prenyl diphosphate synthases, which are classified in a distinct family of prenyltransferase, were demonstrated to accept HMBPP, which implies that the compound is more widely used as a prenyl donor substrate than was previously expected., Published online: 01 Dec 2017. ファイル公開：2018/12/01

The aim of this study was to determine the usefulness of sonography for detecting elbow injuries among young baseball players.One hundred fifty-three volunteers ranging in age from 9 to 12 years and belonging to youth baseball teams participated. Sonography of the elbow was performed in the field when baseball exercises were being conducted. We analyzed the relationship between elbow pain and sonographic abnormalities and the relationship between pitchers and sonographic abnormalities.Sonography showed that 33 subjects had medial epicondylar fragmentation and two had early-stage osteochondritis dissecans of the capitellum. In 25 subjects who agreed to further examination and treatment, radiography confirmed the sonographic findings. All of the 23 subjects with medial epicondylar fragmentation, who stopped throwing, obtained union of the bone and returned to baseball. The two subjects with osteochondritis dissecans of the capitellum underwent surgery before the osteochondral fragment became loosened. Sonographic abnormalities correlated with episodes of elbow pain. Pitchers statistically significantly had sonographic abnormalities.Sonography in the field can provide an opportunity to detect and treat elbow injuries before they become more advanced.

症例1 : 66歳, 男性. 喫煙歴, なし. 2003年1月, 原発性肺腺癌にて右中葉切除術施行. 2004年11月, 再発を認めたため上皮成長因子受容体 (EGFR ) 遺伝子の解析を行った. 変異を認めたためゲフィチニブの投与を行ったところ腫瘍は著明に縮小した. 症例2 : 73歳, 女性. 喫煙歴, なし. 2004年10月, 原発性肺腺癌, T4N2M1 stage IVと診断. 化学療法を行うも, 腫瘍の縮小を認めなかったため, EGFR 遺伝子の解析を行った. 変異を認めたためゲフィチニブの投与を行ったところ腫瘍は縮小した. 症例3 : 51歳, 男性. 喫煙歴, あり. 2004年3月, 原発性肺腺癌, T4N2M1 stage IVと診断. 化学療法を行うも, 有意な腫瘍の縮小を認めなかったため, EGFR 遺伝子の解析を行った. 変異を認めたためゲフィチニブの投与を行ったところ3週後に間質性肺炎を合併したため投与中止となったが, 腫瘍の縮小を認めていた.

d-Serine dehydratase from Saccharomyces cerevisiae (Dsd1p) is a pyridoxal 5'-phosphate (PLP)- and Zn(2+)-dependent enzyme that catalyzes the dehydration of d-serine to yield pyruvate and ammonia. Dsd1p uses the Tyr residue (Y203) to interact with the pyridine nitrogen of PLP, which is a unique feature of PLP enzymes. To investigate the role of Y203 in catalysis, a series of Y203 mutants was constructed and studied. Mutant enzymes possessing a non-polar or a basic residue instead of Y203 (Y203F, A, S and R) exhibited substantial levels of catalytic activity, and among these, the Y203F mutant had the least impact on catalytic activity. The Y203D exhibited a 10(5)-fold decrease in enzyme activity, and unlike wild-type enzyme, the mutant enzyme favoured the Cα reprotonation before hydroxyl group protonation. Our data show that the Y203 does not participate in the protonation of the pyridine nitrogen (N1) of PLP, and Dsd1p uses the cofactor in an N1-unprotonated state. The unprotonated N1 promotes elimination of the leaving group and evades Cα reprotonation before hydroxyl group protonation.

Crystal structures of the ambient pressure and temperature phase (phase I) and high pressure phase (phase II) in CuGeO3 were studied by means of the high pressure single-crystal X-ray diffraction method in a diamond anvil cell using high power X-ray generator and imaging plate detector. The pressure dependence of the atomic displacements in the phase I was investigated under the hydrostatic pressure of 0.1 MPa and 2.9 and 3.9 GPa. The lattice is particularly compressive in the b direction. In phase I the rippled layers are formed by the corner-shared chains of GeO4 tetrahedra and edge-linked planar CuO4. Major effects of pressure, directly related to the shortening of the b-axis, consist of an enhanced folding of the rippled layers towards the b-direction and of a shortening of the weak Cu–O bond. The crystal structure of phase II is monoclinic, a = 4.935(57), b = 6.754(14), c = 6.208(11) A, β = 92.67(3)°, space group; P21/c. The transition from phase I to II involves a corrugated arrangement of the both cation with some oxygens around the c-axis. Ge ion at the transition point of 6.4 GPa changes its coordination number from four-fold to five-fold, and Cu ion occupies a position of seven-fold site. The structure of phase II is explained as a slab structure having unique edge- and corner-sharing arrangements of GeO5 and CuO7 polyhedra. The average Ge–O and Cu–O distances in phase II is 1.92 and 2.17 A, respectively, at 6.5 GPa. Die Kristallstruktur der Hockdruckphase(II) von CuGeO3 Die Kristallstrukturen der Normaldruckphase (Phase I) sowie der Hochdruckphase (Phase II) wurden durch Rontgenstreuung am Einkristall mittels einer Diamandstempelzelle, eines Hochleistungsrontgengenerators und eines Bildplattendetektors bestimmt. Die Druckabhangigkeit der Atomparameter der Phase I wurde bei hydrostatischen Drucken von 0.1 MPa, 2.9 MPa und 3.9 MPa gemessen. Entlang der b-Achse ist das Gitter besonders kompressibel. In der Phase I liegen gewellte Schichten aus Ketten spitzenverknupfter GeO4-Tetraeder und kantenverknupfter planarer CuO4-Einheiten vor. Mit ansteigendem Druck, unmittelbar korreliert mit der Verkurzung der b-Achse, beobachtet man eine zunehmende Faltung dieser Schichten hin zur b-Achse und eine Verkurzung der schwachen Cu–O Bindungen. Phase II kristallisiert monoklin, a = 4.935(57) A, b = 6.754 A, c = 6.208(11) A, β = 92.67°, Raumgruppe P21/c. Die Umwandlung von Phase I zur Phase II beinhaltet eine „wellenformige” Umordnung beider Kationen und einiger Sauerstoffatome um die c-Achse. Das Ge-Ion andert beim kritischen Druck von 6.4 GPa seine Koordinationzahl von vier nach funf, Cu besetzt einen siebenfach koordinierten Platz. Phase II kristallisiert mit einer Schichtstruktur, in der kanten- und spitzenverknupfte GeO5- und CuO7-Polyeder vorliegen. In der Phase II betragen die mittleren Ge–O- und Cu–O-Abstande bei 6.5 GPa 1.92 A und 2.17 A.

An Escherichia coli mutant lacking three major K(+) uptake systems, Trk, Kup, and Kdp, did not grow under low K(+)and high Na(+) concentrations. The introduction of fkuA and of fkuB of a marine bacterium, Vibrio alginolyticus, has been reported to compensate for the growth defect by accelerating the rate of K(+) uptake (Nakamura, Katoh, Shimizu, Matsuba, and Unemoto, Biochim. Biophys. Acta, 1277, 201-208 (1996)). We investigated the function of unknown genes of E. coli, yggS and yggT, homologs of fkuA and fkuB respectively. E. coli TK2420 cells, which lack the three K(+) uptake systems, did not grow under high Na(+) or mannitol concentrations. The growth defect was compensated by the introduction of the yggT gene alone: yggS was not required. Here we found that YggT endowed E. coli cells with a tolerance for osmotic shock, and discuss a possible mechanism.

Objective:Predicted postoperative forcedexpiratory volume in1 s (ppoFEV1)is estimatedinlungcancerpatients beforepulmonaryresection, as well as the clinical stage. This study aims to evaluate ppoFEV1 and ppo-vital capacity (ppoVC) on postoperative day 7 (POD7) and to compare the results following video-assisted thoracic surgery (VATS) and open thoracotomy procedures. Methods: Of the 155 patients who underwent pulmonary resection, 70 had VATS; 30 had muscle-sparing thoracotomy (anterior limiting thoracotomy (AL)); and 55 had postero-lateral thoracotomy (PL). VC and FEV1 were measured on POD7 and compared with the VC and FEV1 before surgery using analysis of covariance (ANCOVA). The ratio of the actual- and the ppoVC and FEV1 was evaluated to identify factors associated with variations in postoperative residual VC/FEV1. Results:There were significant differences by analysis of covariance (ANCOVA) in the VC/FEV1 among the three surgical approaches. In the VATS group, the VC ratio and the FEV1 ratio were 96.5% and 94.7%, respectively; they were significantly higher in the VATS group than in the thoracotomy group (AL: 90.4% and 90.1%, respectively; PL: 87.4% and 87.6%, respectively). Non-chronic obstructive pulmonary disease (COPD) and upper lobectomy were also associated with a low VC ratio and FEV1 ratio. Conclusion: Predicted postoperative pulmonary function might be overestimated in COPD patients or in those undergoing VATS or lower lobectomy. # 2009 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.

Hypothesis There are some risk factors that could predispose a young baseball player to elbow injuries. Materials and methods Study participants were 294 baseball players aged 9 to 12 years old. A questionnaire, physical examination, and ultrasound imaging to investigate elbow injuries were performed. Data for the groups with and without elbow injuries were analyzed statistically using multivariate logistic regression models. Results Ultrasound imaging showed that 60 participants had elbow injuries, including medial epicondylar fragmentation in 58 and osteochondritis dissecans of the capitellum in 2. The odds ratio (95% confidence interval) of the risk factors that statistical analysis showed were significant were age older than 11 years, 2.82 (1.30-6.10); height exceeding 150 cm, 2.02 (1.07-3.82); pitching, 4.50 (2.42-8.37); daily training, 1.96 (1.02-3.79); range of motion (ROM) of external rotation of the shoulder below 130°, 1.98 (1.01-3.87); muscle strength (MS) of external rotation of the shoulder exceeding 80 N, 4.11 (1.47-11.55); and MS of internal rotation of the shoulder exceeding 100 N, 2.04 (1.08-3.90). Discussion Risk factors for elbow injuries are age, height, pitcher, days of training, grip strength, range of motion of external rotation of the shoulder, and muscle strength of the shoulder. Conclusion As new information, our results suggest that decrease of ROM of external rotation of the shoulder and increase of MS of external and internal rotation of the shoulder predispose elbow injuries.

Although distinguishing metastatic colorectal adenocarcinoma from primary lung adenocarcinoma is often difficult, pre- or intra-operative identification is very important, as the resection areas for each diagnosis differ substantially. CDX2, a recently cloned homeobox gene, represents a highly specific and sensitive marker of colorectal adenocarcinoma. We evaluated CDX2 expression using pre- and intra-operative biopsy specimens. The study examined 50 consecutive colorectal adenocarcinoma metastases to the lung, including 20 biopsy specimens and 66 resected specimens, and 21 primary lung adenocarcinomas. All specimens were immunohistochemically stained for CDX2, cytokeratin (CK) 7, CK20 and thyroid transcription factor (TTF)-1, and scored in a semi-quantitative manner. Mean staining score in biopsy specimens was significantly higher for CDX2 than for CK20. Sensitivities for CDX2 and CK7-/20+ in biopsy specimens were 95.0 and 65.0%, respectively. If CDX2 immunostaining had not been performed, 8 biopsy specimens (40%), and 20 resected specimens (30.3%) might have been diagnosed as equivocal cases either as primary lung cancer or metastatic colorectal cancer, using other markers. These results suggest that positive CDX2 staining represents a highly sensitive and specific marker of metastatic colorectal carcinoma in both biopsy and resected specimens, and is superior to staining for the CK7-/20+ phenotype.

A 34-year-old woman presented at our hospital with abdominal distention due to overeating. Acute gastric dilatation was diagnosed. The patient was hospitalized, and nasogastric decompression was initiated. On hospitalization day 3, she developed shock, and her respiratory state deteriorated, requiring intubation and mechanical ventilation. Nasogastric decompression contributed to the improvement in her clinical condition. She was discharged 3 mo after admission. During outpatient follow-up, her dietary intake decreased, and her body weight gradually decreased by 14 kg. An upper gastrointestinal series and endoscopy revealed pyloric stenosis; therefore, we performed gastrojejunostomy 18 mo after her initial admission. The patient was discharged from the hospital with no postoperative complications. Gastric necrosis and perforation due to overeating-induced gastric dilatation are life-threatening conditions. Surgical intervention may be required if delayed pyloric stenosis occurs after conservative treatment. We report a case of pyloric stenosis due to overeating-induced gastric dilatation treated by gastrojejunostomy 18 mo after the initial presentation.