Evidence for mannosidase activities in Streptococcus oralis when grown on glycoproteins as carbohydrate source.
Streptococcus oralis when cultured using ribonuclease B as the sole source of carbohydrate, selectively uses the sugars of the Man5 glycoform as shown by HPAEC and MALDI-TOF mass spectrometric analyses. The organism is able to do this by producing novel alpha-(1-->3), alpha-(1-->6) and beta-(1-->4) mannosidase activities and these act in a concerted manner in what appears as a single-step process. The selective utilisation of Man5 is explained by the absence of an alpha-(1-->2) mannosidase which is required to initiate breakdown of the glycan chains present in the other glycoforms which are components of the glycoprotein.
Tarelli
E
E
Joint Microbiology Research Unit, King's College School of Medicine and Dentistry, London, UK. ted.tarelli@kcl.ac.uk
Byers
H L
HL
Homer
K A
KA
Beighton
D
D
D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002455:Cell Division / Q000502:physiology; D002851:Chromatography, High Pressure Liquid; D006023:Glycoproteins / Q000378:metabolism; D008351:Mannans / Q000737:chemistry; D008361:Mannosidases / Q000378:metabolism*; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000737:chemistry; D012260:Ribonucleases / Q000378:metabolism*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D019533:Streptococcus oralis / Q000201:enzymology*; D013379:Substrate Specificity
D006023:Glycoproteins; D008351:Mannans; D009844:Oligosaccharides; D012260:Ribonucleases; C029600:ribonuclease B; D008361:Mannosidases