DOI: 10.5061/dryad.bcc2fqzr5
title: Data from: Functional role and folding properties of the glucan-binding domain of oral bacterial glucansucrase

description: Streptococcus sobrinus glucansucrase transfers glucose from sucrose to
 dextran and synthesizes water-insoluble glucan by creating α-1,3-branches
 along the dextran polysaccharide. Glucansucrase contains a catalytic
 domain and a glucan-binding domain (GBd) with six tandem repeats. We here
 examined the role of GBd in the glucansucrase, focusing on its impact on
 enzymatic activity, dextran binding, and structural stability. By
 generating seven deletion mutants and a circularly permuted protein, our
 research demonstrates that at least four GBd repeats and proper domain
 orientation are required for efficient glucosyl transfer. Moreover,
 circular dichroism and thermal unfolding analyses revealed that glucosyl
 transfer efficiency is linked to cooperative interdomain folding rather
 than dextran-binding affinity. These findings highlight the importance of
 interdomain allostery in optimizing glucansucrase function.
description: # Data from: Functional role and folding properties of the glucan-binding
 domain of oral bacterial glucansucrase Dataset DOI:
 [10.5061/dryad.bcc2fqzr5](10.5061/dryad.bcc2fqzr5) ## Description of the
 data and file structure Comments and requests should be addressed to
 Hideyuki Komatsu:
 [komatsu@bio.kyutech.ac.jp](mailto:komatsu@bio.kyutech.ac.jp). ### Files
 and variables #### File: Figure1_GTF-I_homology_model_data.py
 **Description:** Homology modeling data of glucosyltransferase (GTF)-I
 based on the *Lactobacillus* GTF-180 crystal structure. The file can be
 visualized by UCSF ChimeraX
 ([https://www.cgl.ucsf.edu/chimerax/](https://www.cgl.ucsf.edu/chimerax/)). #### File: Figure3_GS_activity.csv **Description:** Glucosyl transfer activities plotted against dextran concentration. ##### Variables * Dextran1: dextran concentration in μg/mL for GSdGBd3R, GSdGBd4RS, GSdGBd4RL, GSdGBd5R, and DCP. * GSdGBd3R: glucosyl transfer activities for GSdGBd3R. * GSdGBd4RS: glucosyl transfer activities for GSdGBd4RS. * GSdGBd4RL: glucosyl transfer activities for GSdGBd4RL. * GSdGBd5R: glucosyl transfer activities for GSdGBd5R. * DCP: glucosyl transfer activities for DCP. * Dextran2: dextran concentration in μg/mL for GSdGBd6R and ΔNGBd. * GSdGBd6R: glucosyl transfer activities for GSdGBd6R. * DNGBd: glucosyl transfer activities for ΔNGBd. #### File: Figure4_ITC_summary.csv **Description:** Thermodynamic Parameters of Glucansucrase-mutant Proteins Binding to Dextran in Table 1 and Figure4. ##### Variables * Mutant: name of proteins used. * No.: experiment number. * Temp: temperature in Kelvin. * N: the number of glucose units constituting the dextran stretch. * KGlc: the association constant of a mutant glucansucrase for a* *glucose unit. * DhGlc: enthalpy change for a* *glucose unit in cal. * KDX: the association constant of a mutant glucansucrase for a dextran stretch of *n* glucose units. * DH: enthalpy change for a* *dextran stretch in J. * DG: Gibbs energy changes for dextran-binding of mutant glucansucrase (J). * ]TDS: entropy terms for dextran-binding of mutant glucansucrase (J). * \[protein]: protein concentration (μmol/L). * \[dextran]: daxtran concentration as glucose equivalent concentration (mM). #### File: Figure5A_CD_FarUV_spectra.csv **Description:** Far-UV circular dichroism spectra of glucosyltransferase (GTF)-I proteins. ##### Variables * wavelength: nm * GSd: molar ellipticity of GSd. * GSdGBd2R: molar ellipticity of GSdGBd2R. * GSdGBd3R: molar ellipticity of GSdGBd3R. * GSdGBd4RS: molar ellipticity of GSdGBd4RS. * GSdGBd4RL: molar ellipticity of GSdGBd4RL. * GSdGBd5R: molar ellipticity of GSdGBd5R. * GSdGBd6R: molar ellipticity of GSdGBd6R. * DCP: molar ellipticity of DCP. * DNGBd: molar ellipticity of ΔNGBd. * GBd6R: molar ellipticity of GBd6R. #### File: Figure5B_CD_NearUV_spectra.csv **Description:** Near-UV circular dichroism spectra of glucosyltransferase (GTF)-I proteins. ##### Variables * wavelength: nm * GSdGBd6R: molar ellipticity of GSdGBd6R. * GSdGBd5R: molar ellipticity of GSdGBd5R. * GSdGBd4RL: molar ellipticity of GSdGBd4RL. * GSdGBd4RS: molar ellipticity of GSdGBd4RS. * GSdGBd3R: molar ellipticity of GSdGBd3R. * GSdGBd2R: molar ellipticity of GSdGBd2R. * GSd: molar ellipticity of GSd. * DCP: molar ellipticity of DCP. * DNGBd: molar ellipticity of ΔNGBd. * GBd6R: molar ellipticity of GBd6R. #### File: Figure6_Thermal_unfolding.csv **Description:** Molar ellipticity change upon thermal unfolding of glucosyltransferase (GTF)-I proteins. ##### Variables * temperature: Celsius  * GSd: molar ellipticity of GSd. * GBd6R: molar ellipticity of GBd6R. * GSdGBd6R: molar ellipticity of GSdGBd6R. * GSdGBd5R: molar ellipticity of GSdGBd5R. * GSdGBd4RL: molar ellipticity of GSdGBd4RL. * GSdGBd4RS: molar ellipticity of GSdGBd4RS. * GSdGBd3R: molar ellipticity of GSdGBd3R. * GSdGBd2R: molar ellipticity of GSdGBd2R. * DCP: molar ellipticity of DCP. * DNGBd: molar ellipticity of ΔNGBd. #### File: FigS2_SDS-PAGE.tif **Description:** Images of SDS-PAGE of purified GTF-I mutant proteins. #### File: FigS3_ITC_GSdGBd6R.csv **Description:** ITC raw data and titration curve for GSdGBd6R. ##### Variables * Time: unit in sec * Cp: power in μcal/s * molar ratio: glucose units of dextran/protein * NDH: heat/mole in kcal * Fit: a nonlinear regression curve #### File: FigS3_ITC_GSdGBd5R.csv **Description:**  ITC raw data and titration curve for GSdGBd5R. ##### Variables * Time: unit in sec * Cp: power in μcal/s * molar ratio: glucose units of dextran/protein * NDH: heat/mole in kcal * Fit: a nonlinear regression curve #### File: FigS3_ITC_GSdGBd4RL.csv **Description:**  ITC raw data and titration curve for GSdGBd4RL. ##### Variables * Time: unit in sec * Cp: power in μcal/s * molar ratio: glucose units of dextran/protein * NDH: heat/mole in kcal * Fit: a nonlinear regression curve #### File: FigS3_ITC_GSdGBd4RS.csv **Description:**  ITC raw data and titration curve for GSdGBd4RS. ##### Variables * Time: unit in sec * Cp: power in μcal/s * molar ratio: glucose units of dextran/protein * NDH: heat/mole in kcal * Fit: a nonlinear regression curve #### File: FigS3_ITC_GSdGBd3R.csv **Description:**  ITC raw data and titration curve for GSdGBd3R. ##### Variables * Time: unit in sec * Cp: power in μcal/s * molar ratio: glucose units of dextran/protein * NDH: heat/mole in kcal * Fit: a nonlinear regression curve #### File: FigS3_ITC_GSdGBd2R.csv **Description:**  ITC raw data and titration curve for GSdGBd2R. ##### Variables * Time: unit in sec * Cp: power in μcal/s * molar ratio: glucose units of dextran/protein * NDH: heat/mole in kcal #### File: FigS3_ITC_GSd.csv **Description:**  ITC raw data and titration curve for GSd. ##### Variables * Time: unit in sec * Cp: power in μcal/s * molar ratio: glucose units of dextran/protein * NDH: heat/mole in kcal #### File: FigS3_ITC_DCP.csv **Description:**  ITC raw data and titration curve for DCP. ##### Variables * Time: unit in sec * Cp: power in μcal/s * molar ratio: glucose units of dextran/protein * NDH: heat/mole in kcal * Fit: a nonlinear regression curve #### File: FigS3_ITC_DNGBd.csv **Description:**  ITC raw data and titration curve for ΔNGBd. ##### Variables * Time: unit in sec * Cp: power in μcal/s * molar ratio: glucose units of dextran/protein * NDH: heat/mole in kcal * Fit: a nonlinear regression curve #### File: FigS4_Thermal_spectra_change_GSdGBd6R.csv **Description:** Near-UV CD spectra change of GSdGBd6R on increasing temperature. ##### Variables * Wavelength: in nm * 36: molar ellipticity of GSdGBd6R at 36 °C. * 38: molar ellipticity of GSdGBd6R at 38 °C. * 40: molar ellipticity of GSdGBd6R at 40 °C. * 42: molar ellipticity of GSdGBd6R at 42 °C. * 44: molar ellipticity of GSdGBd6R at 44 °C. * 46: molar ellipticity of GSdGBd6R at 46 °C. * 48: molar ellipticity of GSdGBd6R at 48 °C. * 50: molar ellipticity of GSdGBd6R at 50 °C. * 52: molar ellipticity of GSdGBd6R at 52 °C. * 54: molar ellipticity of GSdGBd6R at 54 °C. * 56: molar ellipticity of GSdGBd6R at 56 °C. * 58: molar ellipticity of GSdGBd6R at 58 °C. * 60: molar ellipticity of GSdGBd6R at 60 °C. * 62: molar ellipticity of GSdGBd6R at 62 °C. * 64: molar ellipticity of GSdGBd6R at 64 °C. * 66: molar ellipticity of GSdGBd6R at 66 °C. #### File: FigS4_Thermal_spectra_change_GSdGBd5R.csv **Description:** Near-UV CD spectra change of GSdGBd5R on increasing temperature. ##### Variables * Wavelength: nm * 36: molar ellipticity of GSdGBd5R at 36 °C. * 38: molar ellipticity of GSdGBd5R at 38 °C. * 40: molar ellipticity of GSdGBd5R at 40 °C. * 42: molar ellipticity of GSdGBd5R at 42 °C. * 44: molar ellipticity of GSdGBd5R at 44 °C. * 46: molar ellipticity of GSdGBd5R at 46 °C. * 48: molar ellipticity of GSdGBd5R at 48 °C. * 50: molar ellipticity of GSdGBd5R at 50 °C. * 52: molar ellipticity of GSdGBd5R at 52 °C. * 54: molar ellipticity of GSdGBd5R at 54 °C. * 56: molar ellipticity of GSdGBd5R at 56 °C. * 58: molar ellipticity of GSdGBd5R at 58 °C. * 60: molar ellipticity of GSdGBd5R at 60 °C. * 62: molar ellipticity of GSdGBd5R at 62 °C. * 64: molar ellipticity of GSdGBd5R at 64 °C. * 66: molar ellipticity of GSdGBd5R at 66 °C. #### File: FigS4_Thermal_spectra_change_GSdGBd4RL.csv **Description:** Near-UV CD spectra change of GSdGBd4RL on increasing temperature. ##### Variables * Wavelength: nm * 36: molar ellipticity of GSdGBd4RL at 36 °C. * 38: molar ellipticity of GSdGBd4RL at 38 °C. * 40: molar ellipticity of GSdGBd4RL at 40 °C. * 42: molar ellipticity of GSdGBd4RL at 42 °C. * 44: molar ellipticity of GSdGBd4RL at 44 °C. * 46: molar ellipticity of GSdGBd4RL at 46 °C. * 48: molar ellipticity of GSdGBd4RL at 48 °C. * 50: molar ellipticity of GSdGBd4RL at 50 °C. * 52: molar ellipticity of GSdGBd4RL at 52 °C. * 54: molar ellipticity of GSdGBd4RL at 54 °C. * 56: molar ellipticity of GSdGBd4RL at 56 °C. * 58: molar ellipticity of GSdGBd4RL at 58 °C. * 60: molar ellipticity of GSdGBd4RL at 60 °C. * 62: molar ellipticity of GSdGBd4RL at 62 °C. * 64: molar ellipticity of GSdGBd4RL at 64 °C. * 66: molar ellipticity of GSdGBd4RL at 66 °C. #### File: FigS4_Thermal_spectra_change_GSdGBd4RS.csv **Description:** Near-UV CD spectra change of GSdGBd4RS on increasing temperature. ##### Variables * Wavelength: nm * 36:  molar ellipticity of GSdGBd4RS at 36 °C. * 38:  molar ellipticity of GSdGBd4RS at 38 °C. * 40:  molar ellipticity of GSdGBd4RS at 40 °C. * 42:  molar ellipticity of GSdGBd4RS at 42 °C. * 44:  molar ellipticity of GSdGBd4RS at 44 °C. * 46:  molar ellipticity of GSdGBd4RS at 46 °C. * 48:  molar ellipticity of GSdGBd4RS at 48 °C. * 50:  molar ellipticity of GSdGBd4RS at 50 °C. * 52:  molar ellipticity of GSdGBd4RS at 52 °C. * 54:  molar ellipticity of GSdGBd4RS at 54 °C. * 56:  molar ellipticity of GSdGBd4RS at 56 °C. * 58:  molar ellipticity of GSdGBd4RS at 58 °C. * 60:  molar ellipticity of GSdGBd4RS at 36 °C. * 62:  molar ellipticity of GSdGBd4RS at 62 °C. * 64:  molar ellipticity of GSdGBd4RS at 64 °C. * 66:  molar ellipticity of GSdGBd4RS at 66 °C. #### File: FigS4_Thermal_spectra_change_GSdGBd3R.csv **Description:** Near-UV CD spectra change of GSdGBd3R on increasing temperature. ##### Variables * Wavelength: nm * 36: molar ellipticity of GSdGBd3R at 36 °C. * 38: molar ellipticity of GSdGBd3R at 38 °C. * 40: molar ellipticity of GSdGBd3R at 40 °C. * 42: molar ellipticity of GSdGBd3R at 42 °C. * 44: molar ellipticity of GSdGBd3R at 44 °C. * 46: molar ellipticity of GSdGBd3R at 46 °C. * 48: molar ellipticity of GSdGBd3R at 48 °C. * 50: molar ellipticity of GSdGBd3R at 50 °C. * 52: molar ellipticity of GSdGBd3R at 52 °C. * 54: molar ellipticity of GSdGBd3R at 54 °C. * 56: molar ellipticity of GSdGBd3R at 56 °C. * 58: molar ellipticity of GSdGBd3R at 58 °C. * 60: molar ellipticity of GSdGBd3R at 60 °C. * 62: molar ellipticity of GSdGBd3R at 62 °C. * 64: molar ellipticity of GSdGBd3R at 64 °C. * 66: molar ellipticity of GSdGBd3R at 66 °C. #### File: FigS4_Thermal_spectra_change_GSdGBd2R.csv **Description:** Near-UV CD spectra change of GSdGBd2R on increasing temperature. ##### Variables * Wavelength: nm * 36: molar ellipticity of GSdGBd2R at 36 °C. * 38: molar ellipticity of GSdGBd2R at 38 °C. * 40: molar ellipticity of GSdGBd2R at 40 °C. * 42: molar ellipticity of GSdGBd2R at 42 °C. * 44: molar ellipticity of GSdGBd2R at 44 °C. * 46: molar ellipticity of GSdGBd2R at 46 °C. * 48: molar ellipticity of GSdGBd2R at 48 °C. * 50: molar ellipticity of GSdGBd2R at 50 °C. * 52: molar ellipticity of GSdGBd2R at 52 °C. * 54: molar ellipticity of GSdGBd2R at 54 °C. * 56: molar ellipticity of GSdGBd2R at 56 °C. * 58: molar ellipticity of GSdGBd2R at 58 °C. * 60: molar ellipticity of GSdGBd2R at 60 °C. * 62: molar ellipticity of GSdGBd2R at 62 °C. * 64: molar ellipticity of GSdGBd2R at 64 °C. * 66: molar ellipticity of GSdGBd2R at 66 °C. #### File: FigS4_Thermal_spectra_change_GSd.csv **Description:** Near-UV CD spectra change of GSd on increasing temperature. ##### Variables * Wavelength: nm * 36: molar ellipticity of GSd at 36 °C. * 38: molar ellipticity of GSd at 38 °C. * 40: molar ellipticity of GSd at 40 °C. * 42: molar ellipticity of GSd at 42 °C. * 44: molar ellipticity of GSd at 44 °C. * 46: molar ellipticity of GSd at 46 °C. * 48: molar ellipticity of GSd at 48 °C. * 50: molar ellipticity of GSd at 50 °C. * 52: molar ellipticity of GSd at 52 °C. * 54: molar ellipticity of GSd at 54 °C. * 56: molar ellipticity of GSd at 56 °C. * 58: molar ellipticity of GSd at 58 °C. * 60: molar ellipticity of GSd at 60 °C. * 62: molar ellipticity of GSd at 62 °C. * 64: molar ellipticity of GSd at 64 °C. * 66: molar ellipticity of GSd at 66 °C. #### File: FigS4_Thermal_spectra_change_GBd6RGSd.csv **Description:** Near-UV CD spectra change of DCP on increasing temperature. ##### Variables * Wavelength: nm * 36: molar ellipticity of DCP at 36 °C. * 38: molar ellipticity of DCP at 38 °C. * 40: molar ellipticity of DCP at 40 °C. * 42: molar ellipticity of DCP at 42 °C. * 44: molar ellipticity of DCP at 44 °C. * 46: molar ellipticity of DCP at 46 °C. * 48: molar ellipticity of DCP at 48 °C. * 50: molar ellipticity of DCP at 50 °C. * 52: molar ellipticity of DCP at 52 °C. * 54: molar ellipticity of DCP at 54 °C. * 56: molar ellipticity of DCP at 56 °C. * 58: molar ellipticity of DCP at 58 °C. * 60: molar ellipticity of DCP at 60 °C. * 62: molar ellipticity of DCP at 62 °C. * 64: molar ellipticity of DCP at 64 °C. * 66: molar ellipticity of DCP at 66 °C. #### File: FigS4_Thermal_spectra_change_DNGBd.csv **Description:** Near-UV CD spectra change of ΔNGBd on increasing temperature. ##### Variables * Wavelength: nm * 36: molar ellipticity of ΔNGBd at 36 °C. * 38: molar ellipticity of ΔNGBd at 38 °C. * 40: molar ellipticity of ΔNGBd at 40 °C. * 42: molar ellipticity of ΔNGBd at 42 °C. * 44: molar ellipticity of ΔNGBd at 44 °C. * 46: molar ellipticity of ΔNGBd at 46 °C. * 48: molar ellipticity of ΔNGBd at 48 °C. * 50: molar ellipticity of ΔNGBd at 50 °C. * 52: molar ellipticity of ΔNGBd at 52 °C. * 54: molar ellipticity of ΔNGBd at 54 °C. * 56: molar ellipticity of ΔNGBd at 56 °C. * 58: molar ellipticity of ΔNGBd at 58 °C. * 60: molar ellipticity of ΔNGBd at 60 °C. * 62: molar ellipticity of ΔNGBd at 62 °C. * 64: molar ellipticity of ΔNGBd at 64 °C. * 66: molar ellipticity of ΔNGBd at 66 °C. #### File: FigS4_Thermal_spectra_change_GBd6R.csv **Description:** Near-UV CD spectra change of GBd6R on increasing temperature. ##### Variables * Wavelength: nm * 20: molar ellipticity of GBd6R at 20 °C. * 25: molar ellipticity of GBd6R at 25 °C. * 30: molar ellipticity of GBd6R at 30 °C. * 35: molar ellipticity of GBd6R at 35 °C. * 40: molar ellipticity of GBd6R at 40 °C. * 45: molar ellipticity of GBd6R at 45 °C. * 50: molar ellipticity of GBd6R at 50 °C. * 55: molar ellipticity of GBd6R at 55 °C. * 60: molar ellipticity of GBd6R at 60 °C. * 65: molar ellipticity of GBd6R at 65 °C. ## Code/software Figure1_GTF-I_homology_model_data.py can be visualized by UCSF ChimeraX ([https://www.cgl.ucsf.edu/chimerax/](https://www.cgl.ucsf.edu/chimerax/)).