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The thermostable endo‐1,5‐α‐l‐arabinanase from Bacillus thermodenitrificans TS‐3 (ABN‐TS) hydrolyzes the α‐1,5‐l‐arabinofuranoside linkages of arabinan. In this study, the crystal structures of inactive ABN‐TS mutants, D27A and D147N, were determined in complex with arabino‐oligosaccharides. The crystal structures revealed that ABN‐TS has at least six subsites in the deep V‐shaped cleft formed across one face of the propeller structure. The structural features indicate that substrate recognition is profoundly influenced by the remote subsites as well as by the subsites surrounding the active center. The 'open' structure of the substrate‐binding cleft of the endo‐acting ABN‐TS is suitable for the random binding of several sugar units in polymeric substrates. Crystal structures of D27A and D147N mutants of the endo‐1,5‐α‐l‐arabinanase from Bacillus thermodenitrificans TS‐3 in complex with arabinohexaose were determined. [ABSTRACT FROM AUTHOR]

The article discusses a study on the high-resolution structure of exo-arabinanase from Penicillium chrysogenum. The authors state that crystallization conditions giving high-quality crystals of Abnx were established successfully by what they call the novel technique referred to as COLAS. They also say that the structures presented in the article could reveal that Abnx has different mechanisms to funnel substrates to the active site and/or to stabilize the transition state compared with the arabinan-degrading enzyme Arb93A.

Porcine pancreatic elastase (PPE) was crystallized under new sulfate-free conditions containing 0.3 M NaCl and 50 m M tris(hydroxymethyl)aminomethane-HCl at pH 7.0. The crystal structure determined at 1.5 Å resolution had a unique conformation in four regions which contained loop portions. A chloride ion was bound near the catalytic triad instead of the sulfate ion in PDB entry , a typical PPE crystal structure. However, the chloride ion did not affect the configuration of the catalytic triad. A tris(hydroxymethyl)aminomethane (Tris) molecule was bound to the S4 and S5 subsites in place of the adjacent molecule in the crystal and played a significant role in the structural change of the region. The distortion in this region may subsequently have induced conformational changes in the other three regions. The fact that Tris and these four regions make a diagonal line in the ac plane may have affected the crystal-packing contraction along the a and c axes in the crystal compared with the typical crystal. [ABSTRACT FROM AUTHOR]

A thermostable endo-1,5-α-L-arabinanase ABN-TS from Bacillus thermodenitrificans TS-3 with a molecular weight of 35 kDa was crystallized by the hanging-drop vapour-diffusion method using sodium citrate as a precipitant. The crystals were loop-mounted in a cryoprotectant solution containing 28%(w/v) sucrose and 1 M sodium citrate pH 6.0 and flash-cooled. Sucrose was selected as the most suitable cryoprotectant. The crystal belonged to the orthorhombic space group P212121, with unit-cell parameters a = 40.3, b = 77.8, c = 89.7 Å. The calculated VM based on one molecule per asymmetric unit was 2.0 ų Da-1. A complete data set from a frozen crystal was collected to 1.9 Å resolution using synchrotron radiation at SPring-8. A molecular-replacement solution was obtained using the structure of α-arabinanase 43A from Cellvibrio japonicus. [ABSTRACT FROM AUTHOR]

Purpose Postoperative infections pose an important problem for patients with cardiac disease. Moreover, oral health status is associated with the risk of longer hospital stays. Therefore, the oral health status of patients was assessed before open-heart surgery. This study aimed to determine the relationship between oral health status and postoperative status. Methods The study included 25 patients who underwent open-heart surgery at our university hospital in 2020. Upon admission, dentists conducted an oral examination and assessed the oral health status of the patients, also using the Japanese version of the Oral Health Assessment Tool (OHAT-J), Revised Oral Assessment Guide (ROAG), oral moisture level, oral bacteria, and other relevant factors. The study investigated the association with postoperative status. Findings Significant postoperative infections were found in patients aged ≥70 years, with an OHAT-J score of ≥5, OHAT-J lip score of ≥1, Streptococcus γ count of 1.0 × 10^6 or higher (CFU/mL), and increased Streptococcus γ before and after surgery. The duration of hospitalization correlated with the OHAT-J, OHAT-J gum and tissue, and ROAG scores. The duration of intensive care unit (ICU) stays correlated with the OHAT-J score. Conclusions The study demonstrates that OHAT-J scores are linked with predicting not just postoperative infection but also the length of hospitalization and ICU stay. As OHAT-J scores do not necessitate specialized dental instruments, they are straightforward and beneficial for healthcare professionals outside of dentistry., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. The Ethics Review Committee for Research in Human Subjects, Showa University Graduate School of Medicine issued approval 3033. The study protocol was performed in accordance with the Declaration of Helsinki. Animal subjects: All authors have confirmed that this study did not involve animal subjects or tissue. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: This study was funded by the Grants-in-Aid for Scientific Research (KAKENHI) - Scientific Research 18K17294. The authors declare no conflicts of interest associated with this manuscript. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Ono et al.)

The gene that encodes a thermostable endo-arabinase (called ABN-TS) from Bacillus thermodenitrificans TS-3 was cloned, sequenced, and expressed in the mesophilic B. subtilis. The gene contained an open reading frame consists of 939 bp, which encodes 313 amino acids. The deduced amino acid sequence of the enzyme showed 50, 46, and 36% similarity with endo-arabinase from B. subtilis IFO 3134 (PPase-C), Pseudomonas fluorescens (ArbA), and Aspergillus niger (ABNA), respectively. The hydrophobic and acidic amino acids making up ABN-TS outnumbered those in PPase-C. The gene product expressed in B. subtilis, as the host, had substantially the same characteristics, and was stable up to 70 degrees C, and the reaction was optimal around 70 degrees C, as well as native ABN-TS.