Understanding Lignin-Degrading Reactions of Ligninolytic Enzymes: Binding Affinity and Interactional Profile

Previous works have demonstrated that ligninolytic enzymes mediated effective degradation of lignin wastes. The degrading ability greatly relied on the interactions of ligninolytic enzymes with lignin. Ligninolytic enzymes mainly contain laccase (Lac), lignin peroxidase (LiP) and manganese peroxidase (MnP). In the present study, the binding modes of lignin to Lac, LiP and MnP were systematically determined, respectively. Robustness of these modes was further verified by molecular dynamics (MD) simulations. Residues GLU460, PRO346 and SER113 in Lac, residues ARG43, ALA180 and ASP183 in LiP and residues ARG42, HIS173 and ARG177 in MnP were most crucial in binding of lignin, respectively. Interactional analyses showed hydrophobic contacts were most abundant, playing an important role in the determination of substrate specificity. This information is an important contribution to the details of enzyme-catalyzed reactions in the process of lignin biodegradation, which can be used as references for designing enzyme mutants with a better lignin-degrading activity

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Is a sustaining rod necessary for diverting loop ileostomy?

Objective: Whether or not a protective stoma reduces the rate of anastomotic leakage after distal colorectal anastomosis is still discussed controversially. It does however facilitate clinical management once leakage has occurred. Loop ileostomies seem to be associated with a lower morbidity and a better quality of life compared to loop colostomies. Generally, diverting loop ileostomies are secured at skin level by means of a supporting device in order to prevent retraction of the ileostomy into the abdomen. However, due to the supporting rod, difficulties may occur in applying a stoma bag correctly and leakage of faeces onto the skin may occur even with correct eversion of the afferent limb. Our aim was to compare morbidity and time to self-sufficient stoma-care in patients having a loop ileostomy with rod to those without rod. Methods: A total of 60 patients necessitating loop ileostomy were analyzed. Patients received surgery in of the two involved institutions according to inhouse standard procedures. 30 patients had an ileostomy with rod (VCHK Inselspital) and a further 30 without rod (KSW Winterthur). Morbidity and time to self-sufficiency regarding stoma care was analyzed during the first 90 postoperative days. Morbidity was determined according to a scoring system ranging from 0 to 4 points for any given set of possible complications (bleeding, necrosis, skin irritation, abscess, stenosis, retraction, fistula, prolapse, parastomal hernia, incomplete diversion), where 0 = no complication and 4 = severe complication. Continuous variables were expressed as median (95% Confidence Interval). For comparisons between the groups the Mann-Whitney U test was used, between categorical variables the X2 test was applied. Results: There were no significant differences in length of hospital stay or time to self-sufficient stoma-care between the groups. Although not significant, patients with a rod ileostomy had a tendency towards more stoma-related complications as well as stoma-related reoperations. The number of patients reaching total self-sufficiency regarding stoma care was higher after rodless ileostomy. Conclusion: According to our data, rodless ileostomies seemto fare just as well as those with a supporting rod, with equal morbidity rates and more patients reaching self-sufficient stoma care. Therefore routine application of a rod for diverting loop ileostomy seems unnecessar