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Objectives: Inguinal hernia (IH) is a common postoperative complication after robot‐assisted radical prostatectomy (RARP). We developed a novel clipping technique for the prevention of IH developing after RARP. Methods: This cohort included 759 consecutive patients who underwent RARP for prostate cancer at the University of Tokyo Hospital between January 2011 and December 2018. We reviewed clinical parameters and identified the risk factors of postoperative IH. The prophylactic preventive procedure of IH development was performed by clipping the peritoneum and underlying tissue around the internal inguinal ring using Hem‐o‐Lok clip to prevent the prolapse of the intestine through the internal inguinal ring. Results: In total, 236 patients received the clipping procedure. The median follow‐up time was 50 months. The incidence rate of IH was 10.8% (78/720). The median time to the diagnosis of IH was 10 months. Univariate analysis revealed that patients with higher age (age ≥ 63), low BMI (BMI < 25 kg/m2), and lower number of surgical experiences (Surgical experience < 40) showed a significantly higher odds ratio of developing IH. Multivariate analysis showed that "BMI < 25 kg/m2" and "Surgical experience < 40" were independent predictive factors of IH. Among the patients with a high risk of IH due to receiving surgery from inexperienced surgeons, there was a statistically significant preventive effect for the patients with "BMI ≥ 25 kg/m2" by the novel clipping procedure. Conclusions: The novel clipping procedure reduced the risk of post‐operative IH in obese patients when the RARP was performed by inexperienced surgeons. [ABSTRACT FROM AUTHOR]

The peptidoglycan of Selenomonas ruminantium is covalently bound to cadaverine (PG-cadaverine), which likely plays a significant role in maintaining the integrity of the cell surface structure. The outer membrane of this bacterium contains a 45-kDa major protein (Mep45) that is a putative peptidoglycan-associated protein. In this report, we determined the nucleotide sequence of the mep45 gene and investigated the relationship between PG-cadaverine, Mep45, and the cell surface structure. Amino acid sequence analysis showed that Mep45 is comprised of an N-terminal S-layer-homologous (SLH) domain followed by [alpha]-helical coiled-coil region and a C-terminal [beta]-strand-rich region. The N-terminal SLH domain was found to be protruding into the periplasmic space and was responsible for binding to peptidoglycan. It was determined that Mep45 binds to the peptidoglycan in a manner dependent on the presence of PG-cadaverine. Electron microscopy revealed that defective PG-cadaverine decreased the structural interactions between peptidoglycan and the outer membrane, consistent with the proposed role for PG-cadaverine. The C-terminal [beta]-strand-rich region of Mep45 was predicted to be a membrane-bound unit of the 14-stranded [beta]-barrel structure. Here we propose that PG-cadaverine possesses functional importance to facilitate the structural linkage between peptidoglycan and the outer membrane via specific interaction with the SLH domain of Mep45. doi: 10.1128/JB.00417-10

Paenibacillus sp. W-61 is capable of utilizing water-insoluble xylan for carbon and energy sources and has three xylanase genes, xyn1, xyn3, and xyn5. Xyn1, Xyn3, and Xyn5 are extracellular enzymes of the glycoside hydrolase (GH) families 11, 30, and 10, respectively. Xyn5 contains several domains including those of carbohydrate-binding modules (CBMs) similar to a surface-layer homologous (SLH) protein. This study focused on the role of Xyn5, localized on the cell surface, in water-insoluble xylan utilization. Electron microscopy using immunogold staining revealed Xyn5 clusters over the entire cell surface. Xyn5 was bound to cell wall fractions through its SLH domain. A [DELTA]xyn5 mutant grew poorly and produced minimal amounts of Xyn1 and Xyn3 on water-insoluble xylan. A Xyn5 mutant lacking the SLH domain (Xyn5[DELTA]SLH) grew poorly, secreting Xyn5[DELTA]SLH into the medium and producing minimal Xyn1 and Xyn3 on water-insoluble xylan. A mutant with an intact xyn5 produced Xyn5 on the cell surface, grew normally, and actively synthesized Xyn1 and Xyn3 on water-insoluble xylan. Quantitative reverse transcription-PCR showed that xylobiose, generated from water-insoluble xylan decomposition by Xyn5, is the most active inducer for xyn1 and xyn3. Luciferase assays using a Xyn5-1uciferase fusion protein suggested that xylotriose is the best inducer for xyn5. The cell surface Xyn5 appears to play two essential roles in water-insoluble xylan utilization: (i) generation of the xylo-oligosaccharide inducers of all the xyn genes from water-insoluble xylan and (ii) attachment of the cells to the substrate so that the generated inducers can be immediately taken up by cells to activate expression of the xyn system. doi: 10.1128/JB.01406-09

The temperate phage [phi]SLT of Staphylococcus aureus carries genes for Panton-Valentine leukocidin. Here, we identify ORF636, a constituent of the phage tail tip structure, as a recognition/adhesion protein for a poly(glycerophosphate) chain of lipoteichoic acid on the cell surface of S. aureus. ORF636 bound specifically to S. aureus; it did not bind to any other staphylococcal species or to several gram-positive bacteria.

Paenibacillus sp. strain W-61, which can utilize xylan as the sole source of carbon and energy, produces extracellular xylanases 1 and 3 (Xyn1 and Xyn3) and cell surface xylanase 5. In this study we found that lppX, immediately downstream of xyn1, encodes a lipoprotein located on the outer layer of the cytoplasmic membrane and that the LppX lipoprotein is essential for the secretion of active Xyn1 across the cytoplasmic membranes. In Escherichia coli, wild-type LppX was destined for the inner layer of the outer membrane. Mutant LppX(C19A), in which Cys-19, a possible lipomodification residue, is replaced with Ala, was located in the periplasm without being anchored to the membranes. Another mutant, LppX(S20D S21D), with substitutions of Asp for Ser-20 and Ser-21 (conversion to an Asp-Asp signal for sorting to the inner membrane), resided on the outer layer of the inner membrane, demonstrating that LppX has the sorting property of a lipoprotein. E. coli harboring both xyn1 and lppX secreted active Xyn1 into the periplasm. In contrast, E. coli carrying xyn1 alone failed to do so, accumulating inactive Xyn1 in the cytoplasmic membranes. Exogenous LppX(C19A) liberated the inactive Xyn1, which had been stagnating in the inner membrane, into the medium as an active enzyme. Thus, we propose that LppX is a novel type of lipoprotein that assists Xyn1 in making the proper fold necessary for traveling across the cytoplasmic membranes to be secreted as an active enzyme.

We have isolated a polylactide or poly(L-lactic acid) (PLA)-degrading bacterium, Amycolatopsis sp. strain K104-1, and purified PLA depolymerase (PLD) from the culture fluid of the bacterium. Here, we cloned and expressed the pld gene encoding PLD in Streptomyces lividans 1326 and characterized a recombinant PLD (rPLD) preparation. We also describe the processing mechanism from nascent PLD to mature PLD. The pld gene encodes PLD as a 24,225-Da polypeptide consisting of 238 amino acids. Biochemical and Western immunoblot analyses of PLD and its precursors revealed that PLD is synthesized as a precursor (prepro-type), requiring proteolytic cleavage of the N-terminal 35-amino-acid extension including the 26-amino-acid signal sequence and 9-residue prosequence to generate the mature enzyme of 20,904 Da. The cleavage of the prosequence was found to be autocatalytic. PLD showed about 45% similarity to many eukaryotic serine proteases. In addition, three amino acid residues, [H.sup.57], [D.sup.102], and S195 (chymotrypsin numbering), which are implicated in forming the catalytic triad necessary for cleavage of amide bond of substrates in eukaryotic serine proteases, were conserved in PLD as residues [H.sup.74], [D.sup.111], and [S.sup.197]. The [G.sup.193] residue (chymotrypsin numbering), which is implicated in forming an oxyanion hole with residue [S.sup.195] and forms an important hydrogen bond for interaction with the carbonyl group of the scissile peptide bond, was also conserved in PLD. The functional analysis of the PLD mutants H74A, D111A, and S197A revealed that residues [H.sup.74], [D.sup.111], and [S.sup.197] are important for the depolymerase and caseinolytic activities of PLD and for cleavage of the prosequence from pro-type PLD to form the mature one. The PLD preparation had elastase activity which was not inhibited by 1 mM elastatinal, which is 10 times higher than needed for complete inhibition of porcine pancreatic elastase. The rPLD preparation degraded PLA with an average molecular mass of 220 kDa into lactic acid dimers through lactic acid oligomers and finally into lactic acid. The PLD preparation bound to high polymers of 3-hydoxy-butyrate, e-caprolacton, and butylene succinate as well as PLA, but it degraded only PLA.

Results point out that the genome organization of the large conjugative plasmid, Rts1, consists of four large modules, suggesting modular gene repertoire evolution of large plasmids. The plasmid is 217,182 basepairs in length containing 300 open reading frames and tus-like genes involved in replication termination.

Research has been conducted on the a phage-tail-like bacteriocin of phytopathogenic Erwinia carotovora subsp. carotovora Er, carotovoricin Er. The binding and killing spectra of the carotovoricin Er preparations for the different bacterium strains have been investigated and the results are reported.