Characterization of Sortase A in Lactobacillus Acidophilus ATCC 4356 Involved in Adherence to Intestinal Cells

Abstract

Aim: Confirmation of the enzymatic activity of Class A sortase (SrtA) in probiotic strain Lactobacillus acidophilus associated with the adhesion properties. Materials & methods: SrtA from L. acidophilus ATCC 4356 was purified and its enzymatic properties was investigated by site-directed mutagenesis approach and the sensitivity to metal ions was also detected. Results: SrtA of L. acidophilus ATCC4356 can recognize LPxTG and LPxTD sorting motifs. The active sites of SrtA include His137, Cys198 and Arg205. Furthermore, acacetin can increase the activity of SrtA, while phenyl vinyl sulfone could effectively inhibit the activity of SrtA with an IC₅₀ of 143.32 μg/ml. The adhesion ability of L. acidophilus was also decreased resulting from the inhibition of SrtA activity. Conclusion: The unique properties of SrtA of L. acidophilus can provide some insights into the development of high-adhesion Lactobacillus strains in the GI tract.

Graphical abstract

A sortase (SrtA) from Lactobacillus acidophilus ATCC 4356 had better adaptability in the acidic environment at 37°C and the inhibition of SrtA can decrease the adhesion related properties of L. acidophilus in vitro. The unique properties of SrtA can provide some insights into the development of high adhesion lactobacillus strains in the GI tract.

Keywords::

• adhesion ability
• L. acidophilus
• sortase inhibitor
• SrtA

Financial & competing interests disclosure

This work was supported by the Natural Science Foundation of China (31601487, 31671869), the Natural Science Foundation of Zhejiang province (LY19C200005), the Research Foundation (Science and Engineering) of Ningbo University (XYL19015) and the K C Wong Magna Fund in Ningbo University. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Additional information

Funding

This work was supported by the Natural Science Foundation of China (31601487, 31671869), the Natural Science Foundation of Zhejiang province (LY19C200005), the Research Foundation (Science and Engineering) of Ningbo University (XYL19015) and the K C Wong Magna Fund in Ningbo University. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.