Have a personal or library account? Click to login
Antimicrobial resistance and virulence genes of Streptococcus agalactiae isolated from mastitis milk samples in China Cover

Antimicrobial resistance and virulence genes of Streptococcus agalactiae isolated from mastitis milk samples in China

Open Access
|Dec 2022

Figures & Tables

Fig. 1

Multiple drug resistance of S. agalactiae shown as antibiotic phenotypic resistance and resistance gene prevalence data. 3 – resistance to 3 classes of antimicrobials; 4 – resistance to 4 classes of antimicrobials; 5 – resistance to 5 classes of antimicrobials; 6 – resistance to 6 classes of antimicrobials; 7 – resistance to 7 classes of antimicrobials; 9 – resistance to 9 classes of antimicrobials
Multiple drug resistance of S. agalactiae shown as antibiotic phenotypic resistance and resistance gene prevalence data. 3 – resistance to 3 classes of antimicrobials; 4 – resistance to 4 classes of antimicrobials; 5 – resistance to 5 classes of antimicrobials; 6 – resistance to 6 classes of antimicrobials; 7 – resistance to 7 classes of antimicrobials; 9 – resistance to 9 classes of antimicrobials

Fig. 2

Positive rate of S. agalactiae resistance genes
Positive rate of S. agalactiae resistance genes

Relationship between drug resistance phenotype and drug resistance genotype of S_ agalactiae

Antibiotic typeResistance geneGenotype (%)
Phenotype resistance rate (%)Consistency rate (%)
Number of bacteriaPositive rate
ermB11/1573.33 91.66
MacrolidesermA10/1566.6780.0083.33
ermC5/1533.33 41.66
LincosamideslnuA9/1560.0066.6789.99
tetM7/1546.67 100.00
tetK6/1540.00 85.71
TetracyclinestetS6/1540.0046.6785.71
tetO5/1533.33 71.42

The combined virulence gene profile of S_ agalactiae

Virulence gene profileDistributiona (%)
glnA+hylB+bibA+iagA+fbsA+clyE3 (20)
glnA+hylB+iagA+fbsA2 (13.33)
bca+glnA+hylB+iagA+fbsA+clyE1 (6.67)
bca+cfb+hylB+bibA+iagA+fbsA+clyE1 (6.67)
bibA+iagA+fbsA+clyE1 (6.67)
bca+hylB+bibA+iagA+fbsA1 (6.67)
hylB+bibA+iagA+fbsA1 (6.67)
bca+bibA+iagA+fbsA1 (6.67)
hylB+bibA+iagA+fbsA+clyE1 (6.67)
cfb+hylB+bibA+iagA+fbsA1 (6.67)
cfb+hylB+bibA+fbsA+clyE1 (6.67)

Primer sequence and reaction conditions of the drug resistance gene of S_ agalactiae

Antimicrobial drug classResistance genePrimer sequence (5′–3′)Annealing temperature (°C)PCR product size (bp)Reference
F: GGTGGCTGGGGGGTAGATGTATTAACTGG
LincosamideslnuAR: GCTCTCTTTGAAATACATGGTATTTTTCGATC56323(23)
F: AACTTAGGCATTCTGGCTCAC
tetOR: TCCCACTGTTCCATATCGTCA50515(29)
F: TCGATAGGAACAGCAGTA
tetKR: CAGCAGATCCTACTCCTT44169(33)
Tetracyclines
tetMF: GTGGACAAAGGTACAACGAG50406
R: CGGTAAAGTTCGTCACACAC
(39)
F: CATAGACAAGCCGTTGACC
tetSR: ATGTTTTTGGAACGCCAGAG48667
ermBF: CGAGTGAAAAAGTACTCAACC48652
R: AGTAACGGTACTTAAATTGTTTAC
F: ATCTTTGAAATCGGCTCAGG
MacrolidesermCR: CAAACCCGTATTCCACGATT47295(32)
F: GTTCAAGAACAATCAATACAGAG
ermAR: GGATCAGGAAAAGGACATTTTAC48421

Minimum inhibitory concentration (MIC) values of, and resistance of S_ agalactiae isolates to, β-lactams, sulfonamides and tetracyclines

Isolate no.MIC (μg/mL)
PENA/CAMPCETOXASMZSXTTEDOX
SH07≤0.125 (S3)1/0.5 (R)≤0.125 (S)32 (R)1 (S)4 (S)0.5/9.5 (S)4 (S)4 (S)
SH07-24 (R)≤0.25/0.12 (S)≤0.125 (S)0.5 (S)16 (R)256 (I)0.25/4.8 (S)16 (R)2 (S)
SH12≤0.125 (S)≤0.25/0.12 (S)0.25 (I)0.5 (S)4 (R)8 (S)0.5/9.5 (S)32 (R)4 (S)
SH33≤0.125 (S)≤0.25/0.12 (S)≤0.125 (S)0.5 (S)16 (R)64 (S)0.5/9.5 (S)32 (R)0.5 (S)
SH45≤0.125 (S)≤0.25/0.12 (S)≤0.125 (S)1 (S)32 (R)64 (S)0.25/4.8 (S)64 (R)2 (S)
HLJ008≤0.125 (S)≤0.25/0.12 (S)≤0.125 (S)32 (R)32 (R)128 (S)0.25/4.8 (S)32 (R)2 (S)
HLJ048-22 (R)≤0.25/0.12 (S)≤0.125 (S)1 (S)4 (R)2 (S)0.5/9.5 (S)16 (R)8 (I)
HLJ030-3≤0.125 (S)≤0.25/0.12 (S)≤0.125 (S)0.5 (S)0.5 (S)64 (S)0.5/9.5 (S)64 (R)4 (S)
NM025≤0.125 (S)≤0.25/0.12 (S)≤0.125 (S)1 (S)1 (S)64 (S)0.25/4.8 (S)32 (R)16 (R)
HB016≤0.125 (S)≤0.25/0.12 (S)≤0.125 (S)0.25 (S)16 (R)128 (S)0.5/9.5 (S)16 (R)4 (S)
NM-2-72-48 (R)≤0.25/0.12 (S)2 (R)1 (S)16 (R)128 (S)0.25/4.8 (S)32 (R)32 (R)
NM-2-034-38 (R)16/8 (R)4 (R)0.5 (S)4 (R)64 (S)2/38 (I)4 (S)4 (S)
SH-2-46-1≤0.125 (S)≤0.25/0.12 (S)≤0.125 (S)0.5 (S)32 (R)128 (S)0.25/4.8 (S)16 (R)4 (S)
SH-2-14-22 (R)4/2 (R)≤0.125 (S)1 (S)16 (R)128 (S)0.25/4.8 (S)32 (R)8 (I)
SD-2-009-2≤0.125 (S)16/8 (R)≤0.125 (S)0.5 (S)4 (R)128 (S)0.25/4.8 (S)8 (I)4 (S)

Drug resistance rate (%) (/15)

S66.67 (10)73.33 (11)80.00 (12)86.67 (13)20.00 (3)93.33 (14)93.33 (14)13.33 (2)73.33 (11)
I0 (0)0 (0)6.67 (1)0 (0)0 (0)6.67 (1)6.67 (1)6.67 (1)13.33 (2)
R33.33 (5)26.67 (4)13.33 (2)13.33 (2)80.00 (12)0 (0)0 (0)80.00 (12)13.33 (2)

Logistic regression analysis of the relationship between antibiotics and virulence genes

Virulence genePenicillinCefoxitinOxacillinDoxycyclineGentamicinClindamycin
BExp(B)PBExp(B)PBExp(B)PBExp(B)PBExp(B)PBExp(B)P
bca40.5374.0280.9991.0993.0001.000−42.4060.0000.9991.0993.0001.000−41.3070.0000.999−61.7990.0000.999
scpB−20.2690.0001.000−60.7180.0000.99962.9162.1080.99919.6993.5901.00062.1059.3690.999−62.4930.0000.999
glnA0.0001.0001.000−19.4110.0000.999−21.8960.0000.999−19.4110.0000.999−19.4110.0000.999−0.6930.5000.744
cfb−0.9340.3931.00042.4062.6100.999−84.8120.0000.999−38.0110.0001.000−80.4170.0000.999−81.8800.0000.999
hylB42.4062.6100.999−40.2090.0000.99942.4062.6100.99940.2092.9000.99940.2092.9000.9990.0001.0001.000
bibA21.2031.6151.000−19.4110.0001.000−21.8960.0001.000−19.4110.0001.000−19.4110.0001.000−42.4120.0000.999
iagA−41.4720.0001.000−1.0990.3331.00042.4062.6101.000−1.0990.3331.00041.3078.6991.000−20.0800.0001.000
cylE0.0001.0001.000−1.0990.3331.00042.4062.6100.999−1.0990.3331.000−1.0990.3331.00021.2031.6151.000

16 kinds of antibacterial drugs and their classification

Drug categoryAntibacterial drugs
penicillin
ampicillin
β-lactamsamoxicillin / clavulanic acid
oxacillin
cefoxitin
Macrolideserythromycin
Lincosamidesclindamycin
Aminoglycosidesgentamicin
Tetracyclinesdoxycycline tetracycline
Chloramphenicolsflorfenicol
Ansamycinsrifampicin
Glycopeptidesvancomycin
Quinolonesciprofloxacin
Sulfonamidessulfisoxazole
sulfamethoxazole

The drug resistance patterns and gene expression profiles of S_ agalactiae

Isolate no.Drug resistance patternResistant geneVirulence gene
SH07(A/C)/CET/ERYermB+lnuA+tetM+tetObca+hylB+bibA+iagA+fbsA
SH07-2PEN/OXA/TE/ERY/CLI/FFCermA+ermB+lnuA+tetM+tetK+tetS+tetOglnA+hylB+iagA+fbsA
SH12OXA/TE/ERY/CLI/GMermA+ermB+ermC+lnuA+tetS+tetObca+glnA+hylB+iagA+fbsA+clyE
SH33OXA/TE/ERY/CLI/GMermA+ermB+ermC+lnuA+tetK+tetS+tetObca+cfb+hylB+bibA+iagA+fbsA+clyE
SH45OXA/TE/ERY/CLIermA+ermB+lnuA+tetK+tetShylB+bibA+iagA+fbsA
HLJ008CET/OXA/TE/ERY/CLIermB+ermA+ermC+lnuA+tetM+tetKglnA+hylB+bibA+iagA+fbsA+clyE
HLJ030-3TE/CLI/FFCermB+ermA+lnuA+tetMhylB+bibA+iagA+ fbsA+clyE
NM025TE/DOX/ERYermA+ermB+lnuA+tetK+tetOglnA+hylB+bibA+iagA+fbsA+clyE
HB016OXA/TE/ERY/CLI/GMermA+ermB+ermC+lnuA+tetM+tetK+tetSglnA+hylB+bibA+iagA+fbsA+clyE
SH-2-46-1OXA/TE/ERYermA+ermB+lnuA+tetOglnA+hylB+iagA+fbsA

Primer sequence and reaction conditions of the virulence gene of S_ agalactiae (13, 22, 23)

Virulence factorVirulence genePrimer sequence (5′–3′)Annealing temperature (°C)PCR size product (bp)
F: CATTGCGTAGTCACCTCCC
β-haemolysin/cytolysiscylER: GGGTTTCCACAGTTGCTTGA54399
F: TAACAGTTATGATACTTCACAGAC ⎕
αC proteinBcaR: ACGACTTTCTTCCGTCCACTTAGG51535
F: CCAAGACTTCAGCCACAAGG
C5a peptidasescpBR: CAATTCCAGCCAATAGCAGC57591
F: ACCGTCTGAAATGATGTGG
Laminin binding proteinlmbR: GATTGACGTTGTCTTCTGC51572
Glutamine synthetaseglnAF: ACGTATGAACAGAGTTGGCTATAA52471
R: TCCTCTGATAATTGCATTCCAC
CAMP factorCfbF: ATGGGATTTGGGATAACTAAGCTAG52193
R: AGCGTGTATTCCAGATTTCCTTAT
HyaluronidasehylBF: ACAAATGGAACGACGTGACTAT52346
R: CACCAATTGGCAGAGCCT
F: AAGCAACTAGAAGAGGAAGC
βC proteinbacR: TTCTGCTCTGGTGTTTTAGG53479
Bacterial immunogenicbibAF: AACCAGAAGCCAAGCCAGCAACC58127
adhesive R: AGTGGACTTGCGGCTTCACCC
F: CGGGATTGATCTAAGTCGCT
Invasion-associated geneiagAR: CCATCAACATCAGTCGCTAA53459
F: AGAGCCAAGTAGGTCAACTTATAG
Fibrin binding protein BfbsAR: TTCATTGCGTCTCAAACCG54290

Minimum inhibitory concentration (MIC) values of, and resistance of S_ agalactiae isolates to, a macrolide, a lincosamide, an aminoglycoside, a quinolone, a chloramphenicol, an ansamycin, and a glycopeptide

Isolate no.MIC (μg/mL)
ERYCLIGMCIPFFCRIFVAN
SH0716 (R)0.25 (S)4 (S)0.5 (S)2 (S)0.5 (S)0.5 (S)
SH07-216 (R)4 (R)4 (S)0.5 (S)16 (R)0.125 (S)0.5 (S)
SH1232 (R)8 (R)16 (R)0.5 (S)4 (S)0.5 (S)0.5 (S)
SH3316 (R)8 (R)16 (R)0.5 (S)8 (I)0.5 (S)0.5 (S)
SH4564 (R)8 (R)2 (S)2 (I)8 (I)0.5 (S)0.5 (S)
HLJ00816 (R)4 (R)4 (S)0.5 (S)4 (S)0.5 (S)0.5 (S)
HLJ048-216 (R)16 (R)8 (I)0.5 (S)4 (S)1 (S)0.5 (S)
HLJ030-30.5 (S)16 (R)2 (S)0.5 (S)16 (R)0.5 (S)0.5 (S)
NM02516 (R)0.5 (S)1 (S)0.5 (S)8 (I)0.5 (S)0.5 (S)
HB01616 (R)4 (R)16 (R)0.5 (S)4 (S)0.5 (S)0.5 (S)
NM-2-72-42 (I)0.5 (S)32 (R)0.5 (S)16 (R)0.5 (S)0.5 (S)
NM-2-034-30.5 (S)16 (R)4 (S)4 (R)16 (R)0.5 (S)0.5 (S)
SH-2-46-116 (R)0.5 (S)4 (S)0.5 (S)4 (S)0.5 (S)0.5 (S)
SH-2-14-216 (R)16 (R)4 (S)4 (R)8 (I)0.5 (S)0.5 (S)
SD-2-009-232 (R)0.5 (S)16 (R)4 (R)16 (R)0.5 (S)0.5 (S)

Drug resistance rate (%) (/15)

S13.33 (2)33.33 (5)60.00 (9)73.33 (11)40.00 (6)100 (15)100 (15)
I6.67 (1)0 (0)6.67 (1)6.67 (1)26.67 (4)0 (0)0 (0)
R80.00 (12)66.67 (10)33.33 (5)20.00 (3)33.33 (5)0 (0)0 (0)
Language: English
Page range: 581 - 590
Submitted on: May 7, 2022
Accepted on: Dec 5, 2022
Published on: Dec 16, 2022
Published by: National Veterinary Research Institute in Pulawy
In partnership with: Paradigm Publishing Services
Publication frequency: 4 times per year

© 2022 Yankun Zhao, Wei Shao, Fulan Wang, Jiaoxiao Ma, He Chen, Shuai Wang, Yating Wu, Cheng Wang, Nan Zheng, Jiaqi Wang, Huimin Liu, published by National Veterinary Research Institute in Pulawy
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.