A multipurpose immobilized biocatalyst with pectinase, xylanase and cellulase activities

<p>Abstract</p> <p>Background</p> <p>The use of immobilized enzymes for catalyzing various biotransformations is now a widely used approach. In recent years, cross-linked enzyme aggregates (CLEAs) have emerged as a novel and versatile biocatalyst design. The present work deals with the preparation of a CLEA from a commercial preparation, Pectinex™ Ultra SP-L, which contains pectinase, xylanase and cellulase activities. The CLEA obtained could be used for any of the enzyme activities. The CLEA was characterized in terms of kinetic parameters, thermal stability and reusability in the context of all the three enzyme activities.</p> <p>Results</p> <p>Complete precipitation of the three enzyme activities was obtained with n-propanol. When resulting precipitates were subjected to cross-linking with 5 mM glutaraldehyde, the three activities initially present (pectinase, xylanase and cellulase) were completely retained after cross-linking. The V_max/K_mvalues were increased from 11, 75 and 16 to 14, 80 and 19 in case of pectinase, xylanase and cellulase activities respectively. The thermal stability was studied at 50°C, 60°C and 70°C for pectinase, xylanase and cellulase respectively. Half-lives were improved from 17, 22 and 32 minutes to 180, 82 and 91 minutes for pectinase, xylanase and cellulase respectively. All three of the enzymes in CLEA could be reused three times without any loss of activity.</p> <p>Conclusion</p> <p>A single multipurpose biocatalyst has been designed which can be used for carrying out three different and independent reactions; 1) hydrolysis of pectin, 2) hydrolysis of xylan and 3) hydrolysis of cellulose. The preparation is more stable at higher temperatures as compared to the free enzymes.</p

Oral Rehabilitation of a child with Chondroectodermal dysplasia (Ellis-van Creveld Syndrome) – A case report

Aims and objectives: This case report aims to describe the dental management strategy of a case of Chondroectodermal dysplasia [Ellis-van Creveld syndrome], an autosomal recessive disorder with the characteristic features of short-limbed dwarfism, postaxial polydactyly, ectodermal and congenital heart defects. Case Description: This case reports presents the dental management a 12 year old girl who reported with the complaint of multiple missing teeth and malformed teeth. The management strategy aimed at aesthetics to improve the social well being of the child. Conclusion: Though few case reports on Ellis Van Creveld syndrome has been reported, managing the oral problems are quiet rare

Relationship between HPV and the biomarkers annexin A1 and p53 in oropharyngeal cancer

BACKGROUND: Human papillomavirus (HPV) is often present in oropharyngeal cancers. Head and neck tumors have been examined for other molecular markers including p53 and annexin A1 (ANXA1). Here, we investigated the prevalence of HPV and its relationship with p53 and ANXA1 in patients with oropharyngeal cancer. METHODS: We have analyzed tumor and adjacent mucosa from 22 patients with squamous cell carcinoma of the oropharynx in addition to samples of the oropharyngeal epithelium in subjects without cancer. We evaluated the presence of the HPV (subtypes 16/18 and 31/33) by chromogenic in situ hybridization. Additionally, we used immunofluorescence to examine the expression of p16, p53, ANXA1 and the phosphorylation of the ANXA1 residues Ser27 (ANXA1-SER) and Tyr21 (ANXA1-TYR). RESULTS: We have detected the presence of HPV genome in 59% of the 22 tumors. Of those, 92% were also positive for p16 immunostaining. Furthermore, we demonstrated a reduction in the expression of p53 in HPV + compared to HPV- tumors. Also, a reduction was observed in the expression of ANXA1 in tumors compared to epithelium from the margins and from controls. We also noted a reduction in ANXA1-TYR in tumors. However, the expression of both ANXA1 and ANXA1-SER were elevated in the margins of the HPV + versus HPV- tumors. CONCLUSIONS: Our results confirm a high prevalence of HPV in oropharyngeal cancer and a reduction in p53 expression in HPV + tumors. We observed a hypoexpression of ANXA1 and ANXA1-TYR in oropharyngeal cancer. The increase in ANXA1-SER in the margins of HPV + tumors suggests that the epithelium in these cases had been activated by an infectious agent. Those findings indicate that ANXA1 and its phosphorylated forms can play important roles in the response to HPV infection and the carcinogenesis of the oropharynx