In JoVE (1)
Articles by Hong L. Yao in JoVE
Determination of Sialic Acids in Liver and Milk Samples of Wild-type and CMAH Knock-out Mice. Cui Cao1, Wen J. Wang1, Ying Y. Huang1, Hong L. Yao1, Louis P. Conway1, Li Liu1, Josef Voglmeir1 1Glycomics and Glycan Bioengineering Research Center (GGBRC), College of Food Science and Technology, Nanjing Agricultural University We describe a HPLC-based method for the determination of N-acetylneuraminic acid and N-glycolylenuraminic acid in mouse liver and milk.
Other articles by Hong L. Yao on PubMed
Biochemical Characterisation of the Neuraminidase Pool of the Human Gut Symbiont Akkermansia Muciniphila Carbohydrate Research. Oct, 2015 | Pubmed ID: 26340137 Since the isolation and identification of Akkermansia muciniphila one decade ago, much attention has been drawn to this gut bacterium due to its role in obesity and type 2 diabetes. This report describes the discovery and biochemical characterisation of all four putative neuraminidases annotated in the A. muciniphila genome. Recombinantly expressed candidate genes, which were designated Am0705, Am0707, Am1757 and Am2085, were shown to cover complementary pH ranges between 4.0 and 9.5. Temperature optima of the enzymes lay between 37 and 42 °C. All four enzymes were strongly inhibited by Cu(2+) and Zn(2+), and loss of activity after the addition of EDTA suggests that all neuraminidases, with the exception of Am0707, require divalent metal ions for their catalytic function. Chemoenzymatically synthesised α2,3- and α2,6-linked indoyl-sialosides were utilised to determine the regioselectivity and substrate promiscuity of the neuraminidases towards C5-modifications of sialic acids with N-acetyl-, N-glycolyl-, N-propionyl-, or hydroxyl-groups. The combination of simple purification procedures and good activities of some of the characterised neuraminidases makes them potentially interesting as tools in bioanalytical or industrial applications.
Quantification of Sialic Acids in Red Meat by UPLC-FLD Using Indoxylsialosides As Internal Standards Glycoconjugate Journal. Apr, 2016 | Pubmed ID: 26969460 Herein we describe a UPLC-FLD-based method for the quantification of the sialic acid content of red meat, using a synthetic neuraminic acid derivative as an internal standard. X-Gal-α-2,6-N-propionylneuraminic acid was synthesized via a chemoenzymatic pathway and its hydrolytic stability was characterized. Known quantities of this compound were incubated with samples of red meat under sialic acid-releasing conditions. The released sialic acids were derivatized, analyzed by UPLC-FLD, and the Neu5Ac/Neu5Gc content of the meat sample was determined by comparison with the internal standard. A number of red meats were analyzed by this method with the following results (Neu5Ac μg/g tissue, Neu5Gc μg/g tissue ± s.d.): pork (68 ± 3, 15.2 ± 0.7), beef (69 ± 8, 36 ± 5), lamb (46 ± 2, 33 ± 1), rabbit (59 ± 2, 0.4 ± 0.4), and hare (50 ± 4, 1 ± 1). We envisage that this methodology will find application in investigating the health effects of dietary Neu5Gc. Graphical abstract ᅟ.