Limits...
Comparing the cariogenic species Streptococcus sobrinus and S. mutans on whole genome level.

Conrads G, de Soet JJ, Song L, Henne K, Sztajer H, Wagner-Döbler I, Zeng AP - J Oral Microbiol (2014)

Bottom Line: It lacks the central competence genes comC, comS, and comR.There are more genes coding for glucosyltransferases and a novel energy production pathway formed by lactate oxidase, which is not found in S. mutans.Both species show considerable differences in the regulation of fructan catabolism.

View Article: PubMed Central - PubMed

Affiliation: Division of Oral Microbiology and Immunology, Department of Operative and Preventive Dentistry & Periodontology, RWTH Aachen University Hospital, Aachen, Germany; gconrads@ukaachen.de.

ABSTRACT

Background: Two closely related species of mutans streptococci, namely Streptococcus mutans and Streptococcus sobrinus, are associated with dental caries in humans. Their acidogenic and aciduric capacity is directly associated with the cariogenic potential of these bacteria. To survive acidic and temporarily harsh conditions in the human oral cavity with hundreds of other microbial co-colonizers as competitors, both species have developed numerous mechanisms for adaptation.

Objectives: The recently published novel genome information for both species is used to elucidate genetic similarities but especially differences and to discuss the impact on cariogenicity of the corresponding phenotypic properties including adhesion, carbohydrate uptake and fermentation, acid tolerance, signaling by two component systems, competence, and oxidative stress resistance.

Conclusions: S. sobrinus can down-regulate the SpaA-mediated adherence to the pellicle. It has a smaller number of two-component signaling systems and bacteriocin-related genes than S. mutans, but all or even more immunity proteins. It lacks the central competence genes comC, comS, and comR. There are more genes coding for glucosyltransferases and a novel energy production pathway formed by lactate oxidase, which is not found in S. mutans. Both species show considerable differences in the regulation of fructan catabolism. However, both S. mutans and S. sobrinus share most of these traits and should therefore be considered as equally virulent with regard to dental caries.

No MeSH data available.


Related in: MedlinePlus

Key differences in competence-related genes between S. mutans and S. sobrinus. Those which are missing in S. sobrinus are crossed off. Adapted from references (47, 48).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4256546&req=5

Figure 0002: Key differences in competence-related genes between S. mutans and S. sobrinus. Those which are missing in S. sobrinus are crossed off. Adapted from references (47, 48).

Mentions: Competence development is a complex process involving sophisticated regulatory networks that trigger the capacity of bacterial cells to take up exogenous DNA from the environment. This phenomenon is frequently encountered in bacteria of the oral cavity, e.g. S. mutans(46). In S. mutans, ComX (or SigX), an alternative sigma factor, drives the transcription of the so-called ‘late-competence genes’ required for genetic transformation. ComX activity is induced by the inputs from two types of signaling pathways, namely the competence-stimulating peptide (CSP)-dependent competence regulation system (‘Classical way’, Fig. 2, left side and Table 3) and the XIP-dependent competence regulation system (‘New way’, Fig. 2, right side, Table 3). ComX and the ‘late-competence genes’ regulated by ComX are highly conserved even between the species, indicating that all MS might have the principal ability to be induced to genetic competence. On the other hand, the upstream signaling pathways, described in-depth below, regulating the activity of ComX show large differences.


Comparing the cariogenic species Streptococcus sobrinus and S. mutans on whole genome level.

Conrads G, de Soet JJ, Song L, Henne K, Sztajer H, Wagner-Döbler I, Zeng AP - J Oral Microbiol (2014)

Key differences in competence-related genes between S. mutans and S. sobrinus. Those which are missing in S. sobrinus are crossed off. Adapted from references (47, 48).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4256546&req=5

Figure 0002: Key differences in competence-related genes between S. mutans and S. sobrinus. Those which are missing in S. sobrinus are crossed off. Adapted from references (47, 48).
Mentions: Competence development is a complex process involving sophisticated regulatory networks that trigger the capacity of bacterial cells to take up exogenous DNA from the environment. This phenomenon is frequently encountered in bacteria of the oral cavity, e.g. S. mutans(46). In S. mutans, ComX (or SigX), an alternative sigma factor, drives the transcription of the so-called ‘late-competence genes’ required for genetic transformation. ComX activity is induced by the inputs from two types of signaling pathways, namely the competence-stimulating peptide (CSP)-dependent competence regulation system (‘Classical way’, Fig. 2, left side and Table 3) and the XIP-dependent competence regulation system (‘New way’, Fig. 2, right side, Table 3). ComX and the ‘late-competence genes’ regulated by ComX are highly conserved even between the species, indicating that all MS might have the principal ability to be induced to genetic competence. On the other hand, the upstream signaling pathways, described in-depth below, regulating the activity of ComX show large differences.

Bottom Line: It lacks the central competence genes comC, comS, and comR.There are more genes coding for glucosyltransferases and a novel energy production pathway formed by lactate oxidase, which is not found in S. mutans.Both species show considerable differences in the regulation of fructan catabolism.

View Article: PubMed Central - PubMed

Affiliation: Division of Oral Microbiology and Immunology, Department of Operative and Preventive Dentistry & Periodontology, RWTH Aachen University Hospital, Aachen, Germany; gconrads@ukaachen.de.

ABSTRACT

Background: Two closely related species of mutans streptococci, namely Streptococcus mutans and Streptococcus sobrinus, are associated with dental caries in humans. Their acidogenic and aciduric capacity is directly associated with the cariogenic potential of these bacteria. To survive acidic and temporarily harsh conditions in the human oral cavity with hundreds of other microbial co-colonizers as competitors, both species have developed numerous mechanisms for adaptation.

Objectives: The recently published novel genome information for both species is used to elucidate genetic similarities but especially differences and to discuss the impact on cariogenicity of the corresponding phenotypic properties including adhesion, carbohydrate uptake and fermentation, acid tolerance, signaling by two component systems, competence, and oxidative stress resistance.

Conclusions: S. sobrinus can down-regulate the SpaA-mediated adherence to the pellicle. It has a smaller number of two-component signaling systems and bacteriocin-related genes than S. mutans, but all or even more immunity proteins. It lacks the central competence genes comC, comS, and comR. There are more genes coding for glucosyltransferases and a novel energy production pathway formed by lactate oxidase, which is not found in S. mutans. Both species show considerable differences in the regulation of fructan catabolism. However, both S. mutans and S. sobrinus share most of these traits and should therefore be considered as equally virulent with regard to dental caries.

No MeSH data available.


Related in: MedlinePlus