Mutation of TonB-Dependent Receptor Encoding Gene MCR_0492 Potentially Associates with Macrolides Resistance in Moraxella catarrhalis Isolates

Figures & data

Figure 1 MALDI-TOF MS results of three isolates; green curve was S18010071_S, the blue curve was R17123922_R, and the red curve was R18013231_R.

Figure 2 The results of genomic extraction and 16sRNA electrophoresis of three isolates. (A) The results of genomic extraction from three isolates. Lane 1: S18010071_S, Lane 2:R17123922_R, Lane 3:R18013231_R, Lane 4: DNA Marker 10,000. (B) The electrophoretic results of the products amplified by 16srDNA universal primers. Lane 1:S18010071_S; Lane 2:R17123922_R; Lanes 3 and 4: R18013231_R, Lane 5: DNA Marker 10,000.

Table 1 The Results of Antimicrobial Susceptibility Testing by Disk Diffusion Method

Strain No.	Erythromycin (S:>21mm)	Results	Azithromycin (S:>26mm)	Results	Clarithromycin (S:>24mm)	Results
S18010071_S	30mm	S	33mm	S	31mm	S
R17123922_R	6mm	NS	6mm	NS	6mm	NS
R18013231_R	6mm	NS	6mm	NS	6mm	NS

Abbreviations: S, susceptible; NS, nonsusceptible.

Table 2 The Results of Antimicrobial Susceptibility Testing by Broth Microdilution Method

Strain No.	Erythromycin (S:≤2μg/mL)	Results	Azithromycin (S:≤0.25μg/mL)	Results	Clarithromycin (S:≤1μg/mL)	Results
S18010071_S	0.25μg/mL	S	0.25μg/mL	S	0.25μg/mL	S
R17123922_R	>512μg/mL	R	>512μg/mL	R	64μg/mL	R
R18013231_R	>512μg/mL	R	>512μg/mL	R	128μg/mL	R

Abbreviations: S, susceptible; R, resistant.

Figure 3 Sequencing depth distribution of Moraxella catarrhalis.

Figure 4 SNV and indel mutations of Moraxella catarrhalis were analyzed by Venn diagram. (A) Results of SNV analysis between two macrolide-resistant Moraxella catarrhalis. (B) Results of indel analysis between two macrolide-resistant Moraxella catarrhalis.

Figure 5 Distribution of SNV and indel in genomes of two macrolide-resistant isolates.

Table 3 Common Site of Indel Mutation in Two Macrolide-Resistant Moraxella catarrhalis

Sample	Gene Name	POS_ALT	Description
R17123922_R	MCR_0492	513364: AGATGGTGCTATT > A	TonB-dependent receptor
R17123922_R	MCR_0492	512447: ACCATCAAT > A	TonB-dependent receptor
R17123922_R	MCR_0492	512148: ACG > A	TonB-dependent receptor
R17123922_R	MCR_0492	512634: T > TGG	TonB-dependent receptor
R17123922_R	MCR_0492	512131: TAA > T	TonB-dependent receptor
R18013231_R	MCR_0492	512442: C > CCAAAGAGA	TonB-dependent receptor
R18013231_R	MCR_0492	512426: ATTCTTCG > A	TonB-dependent receptor
R18013231_R	MCR_0492	512898: GCGT > G	TonB-dependent receptor
R18013231_R	MCR_0492	512635: TCA > T	TonB-dependent receptor
R18013231_R	MCR_0492	513355: TGATG > T	TonB-dependent receptor
R18013231_R	MCR_0492	512153: C > CTG	TonB-dependent receptor
R18013231_R	MCR_0492	512905: G > GATT	TonB-dependent receptor
R18013231_R	MCR_0492	512434: T > TCACCAAA	TonB-dependent receptor
R18013231_R	MCR_0492	513360: A > AG	TonB-dependent receptor
R18013231_R	MCR_0492	512140: A > ACC	TonB-dependent receptor