Capsular polysaccharide production by Streptococcus pneumoniae serotype 1: from strain selection to fed-batch cultivation

Author(s)

Marthos, Bruno Vitorio ^[1] ; Silva Ferri, Anne Leticia ^[1] ; de Figueiredo, Douglas Borges ^[1] ; Zangirolami, Teresa Cristina ^[2] ; Goncalves, Viviane Maimoni ^[1]

Affiliation

^[1] Inst Butantan, Ctr Biotecnol, Lab Bioproc, BR-05503900 Sao Paulo, SP - Brazil

^[2] Univ Fed Sao Carlos, Dept Engn Quim, BR-13565905 Sao Carlos, SP - Brazil

• Document type: Journal article
• Source: Applied Microbiology and Biotechnology; v. 99, n. 24, p. 10447-10456, DEC 2015.
• Web of Science Citations: 1

Abstract

Streptococcus pneumoniae is a human pathogen largely transmitted by aerosols. Vaccines are the main strategy against this pathogen, and the capsular polysaccharide (PS) is its major antigen. S. pneumoniae serotype 1 is associated with large outbreaks and epidemics of invasive diseases. The aims of this work were to screen serotype 1 strains to identify the best PS1 producer, evaluate three peptones for PS1 production, investigate the effects of culture medium components using a design of experiments (DoE), a statistic tool for optimization, and propose a new medium/cultivation strategy. After flask cultivation of nine strains, two that produced high PS1 and biomass values were chosen for further evaluation in the bioreactor, and ST595/01 was chosen as the best PS1 producer strain. Among the peptones tested (Casamino acids, Soytone, and Phytone), the highest PS1 production (298 mg/L) was reached with Phytone. Next, DoE (2(4-1)) was performed to evaluate the effects of yeast extract (YE), Phytone, L-asparagine (Asn), and L-glutamine (Gln), yielding the following results: Phytone presented positive effects (p < 0.05) for maximum production of biomass, PS1, acetate, and lactate; YE showed positive effects for biomass and acid production (p < 0.05); Gln exerted a minor positive effect on PS1 yield factor on glucose (p < 0.1); and Asn presented only an effect on acetate production (p < 0.1). Hence, a new culture medium was formulated based on Phytone, YE, and glucose, and batch and fed-batch cultivations were evaluated. The fed-batch cultivation showed almost 2 times the biomass and 2.5 times the PS1 production as the batch culture, and 8-10 times higher PS1 production than has been previously reported. (AU)

• FAPESP's process: 11/01262-3 - Influence of the storage medium on cell viability and capsular polysaccharide production by Streptococcus pneumoniae
• Grantee: Douglas Borges de Figueiredo
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 08/05207-4 - Pneumococcal conjugate vaccine: capsular polysaccharide - pneumococcal surface protein A
• Grantee: Martha Massako Tanizaki
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 11/02805-0 - Determination of essential amino acids and influence of nitrogenous bases on the continuous cultivation of Streptococcus pneumoniae serotype 14
• Grantee: Anne Leticia Silva Ferri
• Support Opportunities: Scholarships in Brazil - Master
• FAPESP's process: 08/10364-1 - Impact of Streptococcus pneumoniae cultivation strategies on capsular polysaccharide production
• Grantee: Viviane Maimoni Gonçalves
• Support Opportunities: Regular Research Grants