Staphylococcus haemolyticus
| Staphylococcus haemolyticus | |
|---|---|
| |
Scientific classification 
| |
| Domain: | Bacteria |
| Phylum: | Bacillota |
| Class: | Bacilli |
| Order: | Bacillales |
| Family: | Staphylococcaceae |
| Genus: | Staphylococcus |
| Species: | S. haemolyticus
|
| Binomial name | |
| Staphylococcus haemolyticus Schleifer & Kloos, 1975[1]
| |
Staphylococcus haemolyticus is a member of the
biofilms make S. haemolyticus a difficult pathogen to treat.[5] Its most closely related species is Staphylococcus borealis.[9]
Biology and biochemistry
S. haemolyticus is nonmotile,
Growth conditions
Optimal growth occurs between 30 and 40 °C in the presence of
NaCl is poor or absent.[2]
Genome structure
The S. haemolyticus strain JCSC1435 genome contains a 2,685,015
oriC (the origin of chromosomal DNA replication), and these regions are collectively referred to as the “oriC environ”.[10]
As noted, some S. haemolyticus ORFs differ from S. aureus and S. epidermidis. Some of these ORFs encode gene products with known biological features, such as the regulation of
hemolysins.[10]
The S. haemolyticus
antibiotics). The table below contains a list of genes known to be associated with S. haemolyticus antibiotic resistance.[10][11]
| Class | Antimicrobial Agent | MIC (mg/L) | ORF ID | Gene Name | Product | Location |
|---|---|---|---|---|---|---|
Penicillins |
Oxacillin | >512 | SH0091 | mecA | Penicillin-binding protein 2' |
ΨSCCmec(h1435) |
| Ampicillin | 64 | SH1764 | blaZ | β-Lactamase |
Tn552 | |
| methicillin | mecA | Penicillin-binding protein 2' |
ΨSCCmec(h1435) | |||
Cephalosporins |
Ceftizoxime | >512 | SH0091 | mecA | Penicillin-binding protein 2' |
ΨSCCmec(h1435) |
Macrolides |
Erythromycin | >512 | pSHaeB1 | ermC | rRNA adenine N-6-methyltransferase | Plasmid pSHaeB |
| SH2305 | msrSA | ATP-dependent efflux system | πSh1 | |||
| SH2306 | mphBM | Macrolide 2'-phosphotransferase | πSh1 | |||
Quinolones |
Ofloxacin | 8 | SH0006 | gyrA | topoisomerase II) subunit A (point mutation C7313T) |
|
| SH1553 | parC (grlA) | Topoisomerase IV subunit A (point mutation G1598138A) | ||||
Tetracyclines |
Tetracycline | 2 | ||||
| Minocycline | 0.5 | |||||
Aminoglycosides |
Kanamycin |
>512 | SH1611 | aacA-aphD | Bifunctional aminoglycoside N-acetyltransferase and aminoglycoside phosphotransferase | Tn4001 |
| Tobramycin | 16 | SH1611 | aacA-aphD | Bifunctional | Tn4001 | |
| Gentamicin | 64 | SH1611 | aacA-aphD | Bifunctional | Tn4001 | |
Glycopeptides |
Vancomycin | 4 | ||||
| Teicoplanin | 64 | |||||
| Fosfomycin | Fosfomycin | >512 | pSHaeA1 | fosB | Glutathione transferase |
Plasmid pSHaeA |
Cell wall
Like other
N-acetylglucosamine. The major cell wall fatty acids are CBr-15, CBr-17, C18, and C20.[2]
Capsule
Certain strains of S. haemolyticus are capable of producing a
enzymes for a unique trideoxy sugar residue that is N-acylated by aspartic acid.[13]
CP production is influenced by
brain heart infusion broth, or Columbia broth with 2% NaCl favors the production of CP; cultivation on Columbia salt agar plates is suboptimal. Only trace amounts of CP are generated before the end of exponential phase, and the maximal rate of CP production does not occur until early stationary phase.[13]
CP is considered a
polymorphonuclear neutrophil phagocytosis.[citation needed
]
Biofilm formation
The ability to adhere to
medical devices and subsequently form biofilms is a major virulence factor associated with S. haemolyticus.[3][5][14][15] Biofilm formation increases antibiotic resistance[5][14][15] and often leads to persistent infections.[16][17] S. haemolyticus biofilms are not polysaccharide intercellular adhesin (PIA) dependent, and the lack of the ica operon (the gene cluster that encodes the production of PIA) can be used to distinguish S. haemolyticus isolates from other CoNS species.[3][13][15]
Biofilm formation is influenced by a variety of factors including
capsular polysaccharide decreases biofilm formation.[13]
Subinhibitory concentrations (sub
hydrophobic, but they also have an increased level of resistance to dicloxacillin.[14]
Toxins
Some S. haemolyticus strains produce enterotoxins (SE) and/or hemolysins.[10][18] In a study of 64 S. haemolyticus strains, production of SEA, SEB, SEC, and/or SEE was noted (only SED was absent). In addition, 31.3% of the strains were found to produce at least one type of enterotoxin.[18]
Identification
S. haemolyticus can be identified on the species level using a variety of manual and automated methods. The most frequently employed are: the reference method (based on growth tests), API ID 32 Staph (bioMe´rieux), Staph-Zym (Rosco), UZA (a rapid 4-h method), and
gene sequence. Preference towards a particular method usually depends on convenience, economics, and required specificity (some species have identical 16S rRNA).[7][19] The most closely related species of S. haemolyticus is Staphylococcus borealis.[9]
| Method | Tests performed | Interpretation |
|---|---|---|
| Reference | 16 conventional growth tests including: colony pigment, DNase, alkaline phosphatase, ornithine decarboxylase, urease, acetoin production, novobiocin sensitive, polymyxin resistance, and acid production from D-trehalose, D-mannitol, D-mannose, D-turanose, D-xylose, D-cellobiose, maltose, and sucrose | Results are compared to the literature on staphylococcal species[19] |
| API ID 32 Staph (bioMe´rieux) | A bacterial suspension is added to a set of wells containing dried substrates for 26 colorimetric tests. | After 24 hours of incubation at 37 °C, and the addition of a few other reagents, the results are determined by an automated computer using APILAB ID 32 software[19] |
| Staph-Zym (Rosco) | A bacterial suspension is added to minitubes for 10 metabolic or enzymatic tests | The results are determined by color changes, after 24 hours of incubation, and tests for polymyxin and novobiocin susceptibility[19] |
| UZA (a rapid 4-hour method) | This method is a two-step process. Step one consists of three tests measured after four hours incubation at 37 °C: acid production from D-trehalose, urease, and alkaline phosphatase. Step two includes four possible tests, which are administered as needed after 24 hours of incubation at 37 °C. They are: ornithine decarboxylase, novobiocin susceptibility, fosfomycin susceptibility, and anaerobic growth | Results are compared to the literature on staphylococcal species[19] |
| PCR and electrophoresis | Uses gene specific degenerate primers to amplify pieces of DNA, these fragments are resolved using electrophoresis, and then purified for DNA sequencing | Results are determined by a sequence analysis[7] |
Clinical importance
S. haemolyticus is the second-most clinically isolated CoNS (S. epidermidis is the first) and it is considered an important
multi-drug resistant[22] and able to form biofilms, which makes infections especially difficult to treat.[17]
Vascular catheter-associated infections
S. haemolyticus can colonize
β-lactams to work synergistically.[20]
Antibiotic resistance
S. haemolyticus has the highest level of antibiotic resistance among the CoNS.
References
- ISSN 0020-7713.
- ^ ISBN 978-0-387-95041-9.
- ^ PMID 11825946.
- ^ ISBN 978-1-55581-166-2.
- ^ PMID 16880610.
- ^ PMID 16460556.
- ^ PMID 11724835.
- ^ S2CID 25108301.
- ^ S2CID 222320446.
- ^ PMID 16237012.
- S2CID 33021913.
- ^ PMID 8755902.
- ^ PMID 18165309.
- ^ PMID 15980094.
- ^ PMID 19144798.
- PMID 10334980.
- ^ PMID 17850346.
- ^ PMID 2339886.
- ^ PMID 7615705.
- ^ PMID 16801450.
- ISBN 978-0-9631172-1-2.
- ^ PMID 2729941.
- S2CID 22579239.
- PMID 17558874.
- PMID 9449268.
