title: Structural diversity of streptococcal mutans synthesized under different culture and environmental conditions and its effect on mutanase synthesis.
abstract: Streptococcal mutans synthesized under different conditions by growing cultures or by their glucosyltransferases were shown to exhibit a great structural and property diversity. Culturing and environmental factors causing structural differences in mutans were specified. All of the obtained biopolymers (76 samples) were water-insoluble and most of them (72) had a structure with a predominance of α-(1→3)-linked glucose (i.e., the content of α-(1→3)-linkages in the glucan was always higher than 50%, but did not exceed 76%). An exception were four glucans containing more than 50% of α-(1→6)-sequences. In these structurally unique mutans, the ratio of α-(1→3)- to α-(1→6)-bonds ranged from 0.75 to 0.97. Aside from one polymer, all others had a heavily branched structures and differed in the number of α-(1→3), α-(1→6), and α-(1→3,6) linkages and their mutual proportion. The induction of mutanase production in shaken flask cultures of Trichoderma harzianum by the structurally diverse mutans resulted in enzyme activities ranging from 0.144 to 1.051 U/mL. No statistical correlation was found between the total percentage content of α-(1→3)-linkages in the α-glucan and mutanase activity. Thus, despite biosynthetic differences causing structural variation in the mutans, it did not matter which mutan structures were used to induce mutanase production.
authors.affiliation: Department of Industrial Microbiology, Maria Curie-Skłodowska University, Akademicka 19, 20-033 Lublin, Poland. adrianw2@wp.pl
authors.forename: Adrian
authors.initials: A
authors.lastname: Wiater
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Pleszczyńska
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Próchniak
authors.forename: Janusz
authors.initials: J
authors.lastname: Szczodrak
mesh_terms: D003470:Culture Media; D004789:Enzyme Activation; D006026:Glycoside Hydrolases / Q000096:biosynthesis* / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D019906:Nuclear Magnetic Resonance, Biomolecular; D013295:Streptococcus mutans / Q000201:enzymology* / Q000254:growth & development; D013696:Temperature
chemical_list: D003470:Culture Media; D006026:Glycoside Hydrolases; C021780:exo-1,3-alpha-glucanase