Biochemical properties of a novel neoagarotriose-producing β-agarase from Gilvimarinus agarolyticus JEA5

An agar degrading bacterium was isolated from seawater, collected from the east coast of Jeju Island, republic of Korea and identified as Gilvimarinus agarolyticus JEA5. The β-agarase gene from Gilvimarinus agarolyticus JEA5 (rGaa16B) was identified from draft genome sequence by BLAST. Gaa16B has 1800 bp of open reading frame encoding 636 amino acids (aa), and include glycosyl hydrolase family 16 (GH16) β-agarase module and two carbohydrate binding module 6 (CBM6). The Gaa16b was cloned and overexpressed as a MBP-fusion recombinant β-agarase (without signal peptide and two CBM6) in E. coil. rGaa16B showed highest activity at 60°C and pH 7. After incubation at 45OC for 90 min, rGaa16B showed over than 95% of its initial activity. rGaa16B were enhanced in the presence of MnCl2, KCl2, MgCl2, FeSO4. rGaa16B showed 2112.1 unit/mg in the presence of 2.5 mM of MnCl2. rGaa16B produce mainly neoagartetraose (NA4) and neoagarobiose (NA2). Interestingly, we observed neoagartriose (NA3) from hydrolytic products of rGaa16B. LC/Mass analysis was performed to confirm the hydrolytic products containing neoagarotriose. We found three different hydrolytic products which showed 324.28, 468.41, 630.55 Da of molecular weight, respectively. Please click Additional Files below to see the full abstract

Synergistic effect of acetyl xylan esterase on xylanase reaction originated from Ochrovirga pacifica

Acetyl xylan esterase plays an important role in complete enzymatic hydrolysis of lignocellulosic materials into fermentable sugars. It hydrolyzes ester linkages of acetic acid in xylan polysaccharide and supports to enhance the activity of xylanase. This study was conducted to recognize and overexpress the acetyl xylan esterase gene found from Ochrovirga pacifica strain S85 which was isolated from Chuuk state, Micronesia. The genome sequence was analyzed with genome sequencer-FLX and acetyl xylan esterase gene (Axe) was detected. The gene had an open reading frame of 864 bp encoding a polypeptide of 287 amino acids. Theoretical molecular mass and isoelectric point (pI) were 32 kDa and 5.9, respectively. The deduced amino acid sequence of the Axe showed 35.1% similarity with both endo-1,4-β-xylanase B from Robiginitalea biformata HTCC2501. The mature protein displayed the catalytic residues classically found in enzymes belonged to GH16 family. Axe was cloned into pET11a vector and recombinant protein was expressed in E. coli BL21 (DE3), purified by nickel affinity chromatography and its purity was visualized on SDS-PAGE. Commercial xylanase activity was tested after treatment of recombinant acetyl xylan esterase (rAXE) to birchwood xylan substrate. The xylanase activity of rAXE treated sample was about 2 times higher than xylanase only treated sample. Please click Additional Files below to see the full abstract

Recombinant protein production in Escherichia coli by combining of signal peptide originated from Bacillus subtilis

We isolated chitosanase secreting B. subtilis CH2 and identified the chitosanase nucleotide sequence. Analyzed the sequence showed that it consisted of 813 bp, including 87 bp signal sequence. The signal sequence leads the target protein to the cell-membrane of the B. subtilis CH2 and then secret the chitosanase out of the cell. The signal peptide showed 6 amino acids deletion compared to other B. subtilis chitosanase signal peptides. The chitosanase sequence including signal peptide was cloned into pET11a vector without fusion and expressed in E. coli BL21(DE3). The expressed chitosanase in E. coli showed two distinct bands which represent the pro-chitosanase in cytoplasm and mature chitosanase in periplasm. Time frame induction and results showed that muture chitosanase was increased. Subsequently, we linked this chitosanase signal sequence in front of B. subtilis CH2 xylanase and human superoxide distimutase 1 (hSOD1) sequences, and expressed it in E. coli BL21(DE3). The recombinant xylanase and hSOD1 moved to periplasmic space with high efficiency. This signal sequence is useful for bio-medical protein production in E. coli. Please click Additional Files below to see the full abstract

Effect of Diabetes Mellitus on Symptomatic Improvement After Surgery for Benign Prostatic Hyperplasia in Patients With Lower Urinary Tract Symptom and its Relations With Prostatic Urethral Angulation

Purpose To compare improvement of lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia in diabetic versus nondiabetic patients after transurethral resection of the prostate (TURP) or holmium laser enucleation of the prostate (HoLEP). Methods The medical records of 437 patients who underwent TURP or HoLEP at a tertiary referral center from January 2006 to January 2022 were retrospectively analyzed. Among them, 71 patients had type 2 diabetes. Patients in the diabetic mellitus (DM) and non-DM groups were matched 1:1 according to age, baseline International Prostate Symptom Score (IPSS), and ultrasound measured prostate volume. Changes in LUTS were assessed at 3 months after surgery using IPSS and evaluated by categorizing patients according to prostatic urethral angulation (PUA; <50° vs. ≥50°). Medication-free survival after surgery was also investigated. Results No significant differences were noted between the DM and non-DM groups in baseline characteristics except for comorbidities (i.e., hypertension, cerebrovascular disease, and ischemic heart disease, P=0.021, P=0.002, and P=0.017, respectively) and postvoid residual urine volume (115±98 mL vs. 76±105 mL, P=0.028). Non-DM patients showed significant symptomatic improvement regardless of PUA, while DM patients demonstrated improvement in obstructive symptoms only in those with large PUA (≥51°). Among patients with small PUA, DM patients had worse medication-free survival after surgery compared to controls (P=0.044) and DM was an independent predictor of medication reuse (hazard ratio, 1.422; 95% confidence interval, 1.285–2.373; P=0.038). Conclusions DM patients experienced symptomatic improvement after surgery only in those with large PUA. Among patients with small PUA, DM patients were more likely to reuse medication after surgery

A scalable molecule-based magnetic thin film for spin-thermoelectric energy conversion

Spin thermoelectrics, an emerging thermoelectric technology, offers energy harvesting from waste heat with potential advantages of scalability and energy conversion efficiency, thanks to orthogonal paths for heat and charge flow. However, magnetic insulators previously used for spin thermoelectrics pose challenges for scale-up due to high temperature processing and difficulty in large-area deposition. Here, we introduce a molecule-based magnetic film for spin thermoelectric applications because it entails versatile synthetic routes in addition to weak spin-lattice interaction and low thermal conductivity. Thin films of Cr-II[Cr-III(CN)(6)], Prussian blue analogue, electrochemically deposited on Cr electrodes at room temperature show effective spin thermoelectricity. Moreover, the ferromagnetic resonance studies exhibit an extremely low Gilbert damping constant -(2.4 +/- 0.67) x10(-4), indicating low loss of heat-generated magnons. The demonstrated STE applications of a new class of magnet will pave the way for versatile recycling of ubiquitous waste heat

Dilated Cardiomyopathy in a 2 Month-Old Infant: A Severe Form of Hypocalcemia With Vitamin D Deficient Rickets

Dilated cardiomyopathy, which mostly has an idiopathic etiology or is caused by genetic inheritance or infection, can cause irreversible congestive heart failure. Hypocalcemia is a rare etiology of reversible dilated cardiomyopathy. Here we report the case of a two-month-old girl with congestive heart failure who was diagnosed as having dilated cardiomyopathy secondary to hypocalcemia. After calcium and vitamin D replacement therapy, the patient showed a rapid reduction in hypocalcemic tetany and a rapid recovery of left ventricular function. The cause of the hypocalcemia was vitamin D deficient rickets. She was exclusively breast-fed as an infant, and her mother had a vitamin D deficiency and was diagnosed with osteomalacia

Aortic Dissection and Rupture in a Child

After developing sudden severe chest pain, an 11-year-old boy presented to the emergency room with chest pain and palpitations and was unable to stand up. The sudden onset of chest pain was first reported while swimming at school about 30 minutes prior to presentation. Arterial blood pressure (BP) was 150/90 mmHg, heart rate was 120/minute, and the chest pain was combined with shortness of breath and diaphoresis. During the evaluation in the emergency room, the chest pain worsened and abdominal pain developed. An aortic dissection was suspected and a chest and abdomen CT was obtained. The diagnosis of aortic dissection type B was established by CT imaging. The patient went to surgery immediately with BP control. He died prior to surgery due to aortic rupture. Here we present this rare case of aortic dissection type B with rupture, reported in an 11-year-old Korean child

A Case of Laparoscopic Radical Prostatectomy for a Prostatic Stromal Tumor of Uncertain Malignant Potential

Prostatic stromal tumor of uncertain malignant potential (STUMP) is a rare neoplasm with distinctive clinical and pathological characteristics. Here we report a case of laparoscopic radical prostatectomy performed in a patient with prostatic STUMP