Correlation of serum levo-fucose levels as a biomarker with tumor node metastasis staging in oral cancer patients.
Manchil, P. R. D., Joy, E. T., Kiran, M. S., Sherubin, J. E., Khan, M. F. & Aravind, B. S. (2016). Journal of Pharmacy & Bioallied Sciences, 8(Suppl 1), S147-S150.
Background: oral cancer is a result of disordered cellular behavior initiated by various stimuli which is characterized by the alteration of serum glycoproteins consisting of different monosaccharides. One of these is levo-fucose (L-fucose), a methyl pentose. Elevated levels of protein-bound fucose have been reported in various malignancies. Aim: The present study attempted to correlate levels of serum L-fucose as a biomarker with the various tumor node metastasis (TNM) stages of oral cancer. Methodology: The study was carried out on 90 subjects consisting of 30 healthy controls and 60 histopathologically proven oral squamous cell carcinoma (OSCC) cases. The serum fucose level estimation was done based on the method adopted by Winzler. Statistical analysis included independent sample's t-test, one-way ANOVA test, Karl–Pearson correlation test, and Tukey's HSD post hoc test to evaluate the significance and variability of values between groups. Results: Significant elevation in serum fucose levels was noticed among OSCC patients when compared with the controls and a progressive ascent of L-fucose levels were noted as the stage of severity increased. Serum fucose levels were independent of histopathological grading, age, and sex. Conclusion: Serum L-fucose levels were increased in OSCC patients, and a positive correlation was observed between serum L-fucose levels and TNM staging of OSCC. Thus, serum L-fucose can be used as an effective diagnostic and prognostic biomarker in OSCC patients.
Characterization of an α-L-fucosidase from the periodontal pathogen Tannerella forsythia.
Megson, Z. A., Koerdt, A., Schuster, H., Ludwig, R., Janesch, B., Frey, A., Naylor, K., Wilson, I. B. H., Stafford, G. P., Messner, P. & Schäffer, C. (2015). Virulence, 6(3), 282-292.
The periodontal pathogen Tannerella forsythia expresses several glycosidases which are linked to specific growth requirements and are involved in the invasion of host tissues. α-L-Fucosyl residues are exposed on various host glycoconjugates and, thus, the α-L-fucosidases predicted in the T. forsythia ATCC 43037 genome could potentially serve roles in host-pathogen interactions. We describe the molecular cloning and characterization of the putative fucosidase TfFuc1 (encoded by the bfo_2737 = Tffuc1 gene), previously reported to be present in an outer membrane preparation. In terms of sequence, this 51-kDa protein is a member of the glycosyl hydrolase family GH29. Using an artificial substrate, p-nitrophenyl-α-fucose (KM 670 µM), the enzyme was determined to have a pH optimum of 9.0 and to be competitively inhibited by fucose and deoxyfuconojirimycin. TfFuc1 was shown here to be a unique α(1,2)-fucosidase that also possesses α(1,6) specificity on small unbranched substrates. It is active on mucin after sialidase-catalyzed removal of terminal sialic acid residues and also removes fucose from blood group H. Following knock-out of the Tffuc1 gene and analyzing biofilm formation and cell invasion/adhesion of the mutant in comparison to the wild-type, it is most likely that the enzyme does not act extracellularly. Biochemically interesting as the first fucosidase in T. forsythia to be characterized, the biological role of TfFuc1 may well be in the metabolism of short oligosaccharides in the periplasm, thereby indirectly contributing to the virulence of this organism. TfFuc1 is the first glycosyl hydrolase in the GH29 family reported to be a specific α(1,2)-fucosidase.
Cloning, characterization, and production of three α‐L‐fucosidases from Clostridium perfringens ATCC 13124.
Fan, S., Zhang, H., Chen, X., Lu, L., Xu, L. & Xiao, M. (2015). Journal of Basic Microbiology, 56(4), 347-357.
α-L-Fucosidases are key enzymes for the degradation of intestinal glycans by gut microbes. In this work, three putative α-L-fucosidases (Afc1, Afc2, and Afc3) genes from Clostridium perfringens ATCC 13124 were cloned and expressed in Escherichia coli. Afc1 had the α-L-fucosidase domain of glycoside hydrolase (GH) 29 family but showed no enzyme activity toward all the substrates examined. The putative acid/base residue of Afc1, Ser205, was replaced by a glutamic acid which is conserved in GH29-B α-L-fucosidases. However, the mutant Afc1-S205E still failed to show enzyme activity. Afc2 and Afc3 were determined to be 1,3-1,4-α-L-fucosidase of GH29-B subfamily and 1,2-α-L-fucosidase of GH95 family, respectively, and both of them could release fucose from porcine gastric mucin (PGM). When C. perfringens ATCC 13124 grew with the presence of PGM, the transcription of afc1 decreased slightly, while those of afc2 and afc3 increased to 2.2-fold and 1.4-fold, respectively, and the enzyme activities of Afc2 and Afc3 in the culture increased to 2.2-fold and 2.6-fold, respectively. These results suggest that Afc2 and Afc3 are involved in the degradation of intestinal fucosyl glycans by C. perfringens ATCC 13124.