AUTHOR=Liu Tingjun , Liu Jia , Liu Jianwei , Yang Ruiqi , Lu Xianjun , He Xuesong , Shi Wenyuan , Guo Lihong 

TITLE=Interspecies Interactions Between Streptococcus Mutans and Streptococcus Agalactiae in vitro

JOURNAL=Frontiers in Cellular and Infection Microbiology

VOLUME=10

YEAR=2020

URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2020.00344

DOI=10.3389/fcimb.2020.00344

ISSN=2235-2988

ABSTRACT=<p><italic>Streptococcus mutans</italic> is an oral species closely associated with dental caries. As an early oral colonizer, <italic>S. mutans</italic> utilizes interspecies coaggregation to promote the colonization of subsequent species and affect polymicrobial pathogenesis. Previous studies have confirmed several adhering partner species of <italic>S. mutans</italic>, including <italic>Candida albicans</italic> and <italic>Fusobacterium nucleatum</italic>. In this study, we discovered new intergeneric co-adherence between <italic>S. mutans</italic> and the saliva isolate <italic>Streptococcus agalactiae</italic> (GBS-SI101). Research shows that GBS typically colonizes the human gastrointestinal and vaginal tracts. It is responsible for adverse pregnancy outcomes and life-threatening infections in neonates and immunocompromised people. Our results revealed that GtfB and GtfC of <italic>S. mutans</italic>, which contributed to extracellular polysaccharide synthesis, promoted coaggregation of <italic>S. mutans</italic> with GBS-SI101. In addition, oral streptococci, including <italic>Streptococcus sanguinis, Streptococcus gordonii</italic> and <italic>S. mutans</italic>, barely inhibited the growth of GBS-SI101. This study indicated that <italic>S. mutans</italic> could help GBS integrate into the <italic>Streptococcus-</italic>associated oral polymicrobial community and become a resident species in the oral cavity, increasing the risk of oral infections.</p>