Characterization of polysaccharide production of haemophilus influenzae Type b and its relationship to bacterial cell growth.
Haemophilus influenzae type b (Hib) causes invasive infections in infants and young children. Vaccines consisting of Hib capsular polysaccharide (polymer of ribosylribitol phosphate [PRP]) conjugated to a protein are effective in the prevention of such infections. The production of capsular polysaccharide type b was studied in three cultivation conditions: single, glucose pulse, and repeated batch. Specific polysaccharide production (Yp/x) was calculated for all experiments, showing the following values: 67 (single-batch cultivation), 71 (glucose pulse), 75 (repeated-batch cultivation, first batch), and 87 mg of PRP/g of dry cell weight (DCW) (repeated-batch cultivation, second batch). Biomass concentration reached approximately 1.8 g of DCW/L, while polysaccharide concentration was about approximately 132 mg/L in the three fermentation runs. Polysaccharide synthesis is associated with cell growth in all studied conditions as established by Kono's analysis and Luedeking-Piret's model.
D016667:Bacterial Capsules; D001431:Bacteriological Techniques; D018533:Biomass; D019149:Bioreactors; D002455:Cell Division; D005285:Fermentation; D005947:Glucose / Q000378:metabolism; D006192:Haemophilus Infections / Q000378:metabolism*; D018073:Haemophilus Vaccines / Q000096:biosynthesis*; D019741:Haemophilus influenzae type b / Q000254:growth & development / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism; D011135:Polysaccharides, Bacterial / Q000096:biosynthesis*
D018073:Haemophilus Vaccines; C044237:Haemophilus influenzae type b polysaccharide vaccine; D011135:Polysaccharides, Bacterial; D005947:Glucose; D010100:Oxygen