scholarly journals The icaA gene in staphylococci from bovine mastitis

2013 ◽  
Vol 7 (07) ◽  
pp. 556-560 ◽  
Author(s):  
María Valeria Rumi ◽  
Miguel J Huguet ◽  
Adriana B Bentancor ◽  
Elida R Gentilini
Keyword(s):  
Staphylococcus Aureus ◽  
Bovine Mastitis ◽  
Pcr Primers ◽  
Polysaccharide Intercellular Adhesin ◽  
Coagulase Negative Staphylococci ◽  
Biofilm Production ◽  
Consensus Region ◽  
Staphylococcus Spp ◽  
First Time ◽  
Icaa Gene

Introduction: Staphylococcus aureus and coagulase-negative staphylococci (CNS) are frequently isolated from cows with mastitis. A main virulence factor of CNS is the ability to adhere and form biofilms. The intercellular gene cluster adhesion (ica) operon is one factor involved in biofilm production although ica-independent factors are also involved. Previous reports based on the results of S. epidermidis and S. aureus suggested that ica is highly conserved between species, but this detection decreases in other CNS biofilm producers. In this study we evaluated the presence of the icaA gene in strains of Staphylococcus spp. isolated from the milk of bovines with mastitis. Methodology: Thirty-seven staphylococci strains were evaluated by detecting the icaA gene. A new set of PCR primers was designed by consensus region of eight staphylococci from GenBank. Species characterization was performed using the Kloos and Schleifer scheme. Results: We identified the presence of the gene in S. aureus (n:4), S. chromogenes (n:4), and S. sciuri strains (n:2). We also, identified the presence of the gene in S. xylosus (n:5) for the first time. The icaA gene was not detected in S. capitis (n:1), S. epidermidis (n:2), S. hominis (n:2), S. saccharolyticus (n:1), S. simulans (n:4) and S. saprophyticus (n:3). The icaA gene was detected in 40.54% (15/37) of the CNS evaluated. Conclusions: Our results confirm the presence of the ica operon in various species of CNS pointing to polysaccharide intercellular adhesin (PIA) as the most important component for the formation of biofilms.

scholarly journals Staphylococcus spp. Isolated from Bovine Subclinical Mastitis in Different Regions of Brazil: Molecular Typing and Biofilm Gene Expression Analysis by RT-qPCR

Antibiotics ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 888
Author(s):  
Priscila Luiza Mello ◽  
Danilo Flávio Moraes Riboli ◽  
Lisiane de Almeida Martins ◽  
Maria Aparecida Vasconcelos Paiva Brito ◽  
Cassiano Victória ◽  
...  
Keyword(s):  
Biofilm Formation ◽  
Antimicrobial Agents ◽  
Bovine Mastitis ◽  
Subclinical Mastitis ◽  
The Other ◽  
Coagulase Negative Staphylococci ◽  
Expression Of Genes ◽  
Staphylococcus Spp ◽  
Sequence Types ◽  
Icaa Gene

Bovine mastitis is mainly caused by bacteria of the genus Staphylococcus spp., which possess different virulence factors, including the capacity for biofilm formation that provides enhanced protection against the action of immune system components and serves as a barrier against the penetration of antimicrobial agents. This study aimed to characterize 181 Staphylococcus spp. Strains—including Staphylococcusaureus and coagulase-negative staphylococci (CoNS) isolated from bovine subclinical mastitis in six Brazilian states—by molecular methods. RT-qPCR was used to verify the expression of genes of the ica operon—mainly responsible for biofilm formation—as well as bap and bhp. Chromosome similarity among the isolates was investigated by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). The icaA gene was detected in 79 (43.6%) isolates, icaB in 24 (13.2%), icaC in 57 (31.4%), and icaD in 127 (70.1%). The bap gene was identified in 66 (36.4%) isolates, while the bhp gene was found in nine (4.9%). RT-qPCR confirmed the expression of the icaA gene in 60 (75.9%) isolates, of icaB in six (25%), of icaC in 26 (45.6%), and of icaD in 80 (63%). Clonal typing of the isolates by PFGE permitted the identification of eight Staphylococcusaureus clusters that simultaneously included ≥3 strains, with a similarity of ≥80%. Regarding the other species studied, three clusters were observed for Staphylococcuschromogenes and four clusters for Staphylococcusepidermidis. Only one cluster each was identified for Staphylococcussaprophyticus and Staphylococcussimulans, while the other species did not form any cluster. With respect to MLST, ST126 and ST1 were the prevalent sequence types in S. aureus, while in S.epidermidis all sequence types were different. These results reveal strains with the same evolutionary origin as other isolates, which might cause infections in humans and animals, suggesting their ability to spread between these species.

scholarly journals Virulence Factors in Staphylococcus Associated with Small Ruminant Mastitis: Biofilm Production and Antimicrobial Resistance Genes

Antibiotics ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 633
Author(s):  
Nara Cavalcanti Andrade ◽  
Marta Laranjo ◽  
Mateus Matiuzzi Costa ◽  
Maria Cristina Queiroga
Keyword(s):  
Antimicrobial Resistance ◽  
Virulence Factors ◽  
Animal Species ◽  
Susceptibility Testing ◽  
Small Ruminant ◽  
Coagulase Negative Staphylococci ◽  
Biofilm Production ◽  
Antimicrobial Resistance Genes ◽  
Staphylococcus Spp ◽  
Icaa Gene

Small ruminant mastitis is a serious problem, mainly caused by Staphylococcus spp. Different virulence factors affect mastitis pathogenesis. The aim of this study was to investigate virulence factors genes for biofilm production and antimicrobial resistance to β-lactams and tetracyclines in 137 staphylococcal isolates from goats (86) and sheep (51). The presence of coa, nuc, bap, icaA, icaD, blaZ, mecA, mecC, tetK, and tetM genes was investigated. The nuc gene was detected in all S. aureus isolates and in some coagulase-negative staphylococci (CNS). None of the S. aureus isolates carried the bap gene, while 8 out of 18 CNS harbored this gene. The icaA gene was detected in S. aureus and S. warneri, while icaD only in S. aureus. None of the isolates carrying the bap gene harbored the ica genes. None of the biofilm-associated genes were detected in 14 isolates (six S. aureus and eight CNS). An association was found between Staphylococcus species and resistance to some antibiotics and between antimicrobial resistance and animal species. Nine penicillin-susceptible isolates exhibited the blaZ gene, questioning the reliability of susceptibility testing. Most S. aureus isolates were susceptible to tetracycline, and no cefazolin or gentamycin resistance was detected. These should replace other currently used antimicrobials.

scholarly journals Case Study: Misdiagnosis of Nonhemolytic Staphylococcus aureus Isolates from Cases of Bovine Mastitis as Coagulase-Negative Staphylococci

Animals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 252
Author(s):  
Valerie E. Ryman ◽  
Felicia M. Kautz ◽  
Steve C. Nickerson
Keyword(s):  
Staphylococcus Aureus ◽  
Bovine Mastitis ◽  
Dairy Farm ◽  
Blood Agar ◽  
Coagulase Negative Staphylococci ◽  
Mannitol Salt Agar ◽  
Lactating Cows ◽  
Presumptive Identification ◽  
Microbiological Techniques

Staphylococcus aureus is one of the most concerning mastitis-causing pathogens in dairy cattle. Using basic microbiological techniques, S. aureus is typically identified by colony characteristics and hemolysis on blood agar where isolates without hemolysis are typically considered to be coagulase-negative staphylococci (CNS) isolates. Herein, we present a decade-long case study where suspected S. aureus isolates from one Georgia dairy farm were further tested to confirm presumptive identification. Presumptive identification of bacterial growth from 222 mammary secretions from bred Holstein heifers and lactating cows was conducted at the time of collection. Presumptive identification of S. aureus on blood agar was based on observation of colony morphology, color, and presence or absence of a broad zone of incomplete hemolysis and a smaller zone of complete hemolysis at 48 h. Those without hemolysis were presumptively characterized as CNS. All isolates were further plated on mannitol salt agar and a coagulase test was performed. A positive for both of these tests together was deemed to be S. aureus. A selection of isolates was tested using API® Staph to biochemically confirm S. aureus identification. Data showed that 63.96% of isolates presumed to be CNS isolates were identified as S. aureus, 9.46% of isolates presumed to be CNS isolates were identified as coagulase-positive staphylococci (CPS) species (but not S. aureus), and 26.58% of samples that were presumed to be CNS isolates were identified correctly.

scholarly journals Expression of icaA and icaD genes in biofilm formation in Staphylococcus aureus isolates from bovine subclinical mastitis

2021 ◽  
Vol 41 ◽  
Author(s):  
Viviane F. Marques ◽  
Huarrisson A. Santos ◽  
Thomas H. Santos ◽  
Dayanne A. Melo ◽  
Shana M.O. Coelho ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Biofilm Formation ◽  
Phenotypic Expression ◽  
Bovine Mastitis ◽  
Subclinical Mastitis ◽  
Transcriptional Analysis ◽  
Important Species ◽  
High Prevalence ◽  
Staphylococcus Spp

ABSTRACT: Staphylococcus spp. plays a significant role in the etiology of bovine mastitis. Staphylococcus aureus is considered the most important species due to the high prevalence and the difficulty of in vivo treatment that is related to the expression of virulence factors and biofilm formation. This study aimed to detect the phenotypic expression of the biofilm formation in 20 S. aureus isolated from bovine mastitis and to evaluate the expression and regulation of genes involved in its production. MALDI-TOF and phenogenotypic identification assays were performed to characterize the isolates. The phenotypic biofilm production and the presence of icaA and icaD and bap genes were evaluated. The Agr system was typified (agr I, agr II, agr III and agr IV) and its regulator (agr RNAIII) was detected. Furtherly, Real-time PCR (qPCR) was performed at chosen times to quantify the expression of icaA, icaD and hld genes in three selected isolates. All 20 strains were biofilm producers and most presented icaA and icaD genes. Only one isolate presented the bap gene. The agr gene type II showed a prevalence of 70%. Transcriptional analysis revealed increased expression of ica genes at eight hours of growth. These results confirm that polysaccharides production mediated by the icaADBC operon genes is an essential mechanism to the biofilm formation and contributes to the early stages of bacterial growth.

scholarly journals Phenotypic and Genotypic Characteristics and Resistance Profile of Staphylococcus spp. from Bovine Mastitis

2020 ◽  
Vol 48 ◽  
Author(s):  
Érica Chaves Lucio ◽  
Gisele Veneroni Gouveia ◽  
Mateus Matiuzzi Da Costa ◽  
Mário Baltazar De Oliveira ◽  
Rinaldo Aparecido Mota ◽  
...  
Keyword(s):  
Antimicrobial Resistance ◽  
Milk Production ◽  
Biofilm Formation ◽  
Negative Impact ◽  
Meca Gene ◽  
Bovine Mastitis ◽  
Resistant Bacteria ◽  
Production Chain ◽  
Biofilm Production ◽  
Staphylococcus Spp

Background: Bovine mastitis remains one of the health problems that cause the most damage to milk producers. The negative impact of mastitis is due to reduced milk production, early slaughter of females, reduced commercial value of the affected animals, losses in the genetic potential of the herd, expenses with medicines and veterinary medical assistance. Staphylococcus spp. stands out as the cause of this disease and has been able to remain in the mammary gland, becoming resistant to several antimicrobials. The aims of the present study were to characterize the phenotypes, genotypes and resistance profiles of Staphylococcus spp. isolates from bovine mastitis cases in the state of Pernambuco, Brazil.Materials, Methods & Results: These isolates were classified according to biochemical tests and the presence of the nuc gene.  The polymerase chain reaction (PCR) for amplification of the mecA and blaZ genes was used to analyze the genetic potentials of antimicrobial resistance. Isolates were also phenotypically tested for resistance to nine antimicrobials (ampicillin, doxicillin, erythromycin, gentamicin, rifampicin, cephalothin, amoxicillin, nalidixic acid and oxacillin). The genetic potentials for biofilm production were evaluated by the amplifications of the icaD, icaA and bap genes. The phenotypic test of gentian violet was used for biofilm formation analyzes. Ninety-three (93.0%) of the isolates among the Staphylococcus spp. samples were classified as Staphylococcus aureus. The lowest percentage of sensitivity observed was for amoxicillin (28.0%). All of the isolates were sensitive to erythromycin and gentamicin, and 15 (15%) exhibited sensitivity to all of the drugs tested. All of the isolates were negative for the mecA gene, and 36 (36%) were positive for blaZ. In the adhesion microplate tests, 44 (44%) of the isolates were capable of biofilm formation. Of these, seven (15.9%) were strong formers, whereas 16 (36.3%) and 21 (47.8%) were moderate and weak formers, respectively. The icaD gene was confirmed in 89 (89%) of the isolates. The icaA gene was confirmed in 61 (61%) samples, and the bap gene in 52 (52%) samples. One of the samples did not possess icaA, icaD or bap and exhibited moderate biofilm formation according to the microplate adherence test. Sixteen isolates simultaneously exhibited the three genes tested for biofilm production (icaA, icaD and bap) and were negative according to the microplate adherence test.Discussion:  The indiscriminate use of antibiotics to treat mastitis is a common practice in the study area, which may have contributed to the high proportion of herds (88.23%; 15/17) with multi-resistant isolates, constituting a selection factor for the dissemination of resistant bacteria among herds.  The absence of the mecA gene in the present study may be associated with the development of resistant bacteria through another mechanism, such as the overproduction of beta-lactamases. The results demonstrate that antimicrobial resistance occurs in Staphylococcus spp. that cause bovine mastitis in herds of Pernambuco and that these isolates have the a great capacity for biofilm formation. It is necessary to sensitize the professionals involved in the milk production chain of Brazil regarding the importance of the adequate use of antimicrobials for the treatment and control of mastitis, since studies in the country indicate the dissemination of resistant bacterial strains.

scholarly journals Staphylococcus aureus and bovine mastitis: molecular typing of methicillinresistance and clinical description of infected quarters

2019 ◽  
Vol 70 (2) ◽  
pp. 1511
Author(s):  
Α. OREIBY ◽  
H. KHALIFA ◽  
A. EID ◽  
A. AHMED ◽  
T. SHIMAMOTO ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Methicillin Resistance ◽  
Animal Health ◽  
Bovine Mastitis ◽  
Clinical Signs ◽  
Subclinical Mastitis ◽  
Clinical Severity ◽  
Resistance Pattern ◽  
Gram Positive ◽  
Staphylococcus Spp

This study targeted Staphylococcus aureus (S. aureus)-mastitis of bovine as a possible source of livestock-associated methicillin-resistant Staphylococcus aureus (MRSA), to describe clinical signs of mastitis associated with MRSA and methicillin-sensitive Staphylococcus aureus (MSSA). The study area was the Gharbia and Kafrelsheikh governorates, in the central and northern regions of the Egyptian Delta. Clinical examination of animals was performed to detect clinical mastitis (CM) and clinically normal cases were tested by the California mastitis test (CMT) to identify subclinical mastitis (SCM). Accordingly, 38 mastitis cases (68 infected quarters) were detected. Milk samples were collected aseptically and were cultured on Baird Parker agar. Fifty nine Gram-positive cocci-shaped isolates were selected and preserved. In addition, 33 Staphylococcus spp. isolates originated from bovine mastitis at the same study area were obtained from Animal Health Research Institute (AHRI). The cocci-shaped Gram-positive bacteria and AHRI Staphylococcus spp. isolates were used for molecular identification of S. aureus and MRSA. Molecular screening had yielded 17 S. aureus isolates, from which five isolates (29.41%) were MRSA and 12 isolates (70.59%) were MSSA. The five MRSA isolates were mecA positive, but mecC negative. Multilocus sequence typing (MLST) of the five MRSA isolates indicated that all were sequence type 1 (ST1). S. aureus-associated cases showed different clinical forms of mastitis, including subclinical, acute, chronic, and gangrenous. However, subclinical mastitis was the only detected form associated with MRSA, which may represent a potential hidden risk for humans. Phenotypic antimicrobial resistance pattern of MRSA isolates showed resistance to all of the tested β-lactam antimicrobials, with marked orgaresistance to tetracycline and gentamycin. Based on our knowledge, this is the first report to identify MRSA ST1 in Egypt. Bovine mastitis could be a source for the dissemination of MRSA to humans and other animals. Additionally,while methicillin-resistance may have no effect on the clinical severity of mastitis, it does affect therapeutic success, particularly when β-lactam antimicrobials are used.

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