Saturday 28 May 2016

Staphylococcus aureus (S. aureus)

Historical perspectives and milestones:-

Staphylococcus [staffʺə-lo kokʹəs]
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3810938/pdf/ET-1909.pdf

From the Greek staphyle (bunch of grapes) and kokkos (berry), Staphylococcus is a genus of gram-positive spherical bacteria that commonly cause surgical and skin infections, respiratory disease, and food poisoning.

In 1880, Scottish surgeon Sir Alexander Ogston (1844-1929) first described staphylococci in pus from a surgical abscess in a knee joint: “the masses looked like bunches of grapes.”

In 1884, German physician Friedrich Julius Rosenbach* isolated and differentiated 2 strains of staphylococci colonies by their color: S. aureus (from the Latin aurum, gold) and S. albus (Latin for white). S. albus was later renamed S. epidermidis.

*Anton J. Rosenbach (1842-1923), a German surgeon

  1. Accidental discovery of penicillin by Fleming
  2. Dr Mathews Duncan first used the term 'sapraemia' to describe bacterial chemical poisoning.
  3. Papers published on Micrococcus Poisoning by Sir Alexander Ogston in 1882, Scottish surgeon to the Aberdeen Royal Infirmary
   
       4. Discovery of Staphylococcus aureus by Rosenbach in 1884
The type strain of S. aureus subsp. aureus Rosenbach 1884 (DSM 20231T) was first isolated in 1884 from human pleural fluid by Rosenbach.
      5. Earlier synonyms for Staphylococcus aureus: 
Staphylococcus pyogenes aureus
Staphlococcus pyogenes citreus
Micrococcus pyogenes
Micrococcus aureus    
      6. Misnomer: Streptococcus aureus
      7. Earlier authority:
 Staphylococcus aureus Rosenbach 1884
"Staphylococcus pyogenes aureus" Rosenbach 1884
"Staphlococcus pyogenes citreus" Passet 1885
"Micrococcus pyogenes" Lehmann and Neumann 1896
"Micrococcus aureus" (Rosenbach 1884) Zopf 1885

Staphylococcus aureus (S. aureus) classification:
http://www.gbif.org/species/3227657
  • Kingdom: Bacteria
  • Phylum: Firmicutes
  • Class: Bacilli
  • Order: Bacillales
  • Family: Staphylococcaceae
  • Genus: Staphylococcus
  • Species: Staphylococcus aureus
  • Full name: Staphylococcus aureus Rosenbach, 1884
  • Common name: Methicillin-resistant Staphylococcus aureus (MRSA)

Staphylococcus aureus (S. aureus) - Overview
  1. Places found - nasal passages (nasal tract; nose), respiratory tract, skin
  2. Gram stain: Gram +
  3. Catalase test: +
  4. Shape: coccus (round)
  5. Pigment: staphyloxanthin (golden)
  6. Morphology:
  7. Colony morphology: smooth round colonies
  8. Spore formation: non-spore forming
  9. Motility: non-motile
  10. Forms spreading dendrites
  11. Bacteria photo gallery

S. aureus epidemiology:-
  • Human indigenous bacterium; 30% healthy human harbour it in their nasal passages
  • Not always pathogenic
  • Can become pathogenic
  • Major cause of staphylococcal disease
  • Now have MRSA, which are resistant to antibiotics
  • Between 1963-2012, there were 3085 cases involving MRSA reported worldwide
  • Penicillin was discovered just before WWII  ended in 1945
  • There is no mention of year/date before 1944 ... listed as N/A online  
  • India: Undated (1); 2007 (1); 2012 (many cases) 
  • UK: Undated (1); 2012 (1)
  • Palestine: 2012 (1)
  • Mexico: 2012 (1)
  • USA: Undated (8); 1963 (2); 2005 (114); 2011 (many cases)
  • China: 1997 (125); 2002 (89); 2007 (203); 2010 (1); 2011 (1)
  • Chinese Taipei: 2000 (20); 2006 (1)
  • Belgium: 2011 (1)
  • Brazil: 2007 (7)
  • Poland: Undated (47); 1996 (6); 1997 (6); 1998 (4); 1999 (1,087); 2000 (44); 2001 (10); 2002 (20); 2003 (8)
  • Germany: Undated (3)
  • Australia: Undated (1); 1973 (201)
  • Czech Republic: Undated (12)
  • Republic of Korea: Undated (3) 
  • French Guiana: Undated (1) 
  • Netherlands: Undated (2) 
  • United Republic of Tanzania: Undated (2) 
  • Islamic Republic of Iran: Undated (1) 
  • Japan: Undated (1) 

S. aureus infections:-
  1. Skin infections - causes abscess; eczema
  2. Respiratory infections - causes sinusitis; infect in-dwelling catheters
  3. Bloodstream - causes bacteremia
  4. Contaminated food - causes food poisoning
S. aureus virulence:-
  1. Cigarette smoke boosts S. aureus virulence
  2. Emerging public threat - methicillin-resistant Staphylococcus aureus (MRSA) infection
S. aureus in clinical medicine:-
  1. Clinical management of Staphylococcus aureus bacteremia in adults
  2. S. aureus clinical isolates - from in-dwelling catheters
  3. The emergence of antibiotic-resistant forms of pathogenic S. aureus (MRSA) is a worldwide problem in clinical medicine.
S. aureus fatalities:-
  1. in pediatric patients (less virulent)
  2. in adults (more virulent)
S. aureus research on molecular genetics:-
  1. Genome
S. aureus has a genome size of approximately 2.8 Mb, with a GC content of 32%. The chromosome contains pathogenicity islands and antibiotic resistance genes acquired through horizontal gene transfer of mobile genetic elements (MGEs). The MGEs occupy 15% to 20% of the chromosome. During outbreaks, S. aureus genomes develop single nucleotide polymorphisms (SNPs) and small genetic rearrangements and acquire or lose MGEs containing resistance or virulence genes. 
      2. First complete genome sequence 2015
Genome Announc. 2015 Jul-Aug; 3(4): e00800-15.Published online 2015 Jul 16. doi: 10.1128/genomeA.00800-15PMCID: PMC4505135
First Complete Genome Sequences of Staphylococcus aureus subsp. aureus Rosenbach 1884 (DSM 20231T), Determined by PacBio Single-Molecule Real-Time Technology.Akino Shiroma, Yasunobu Terabayashi, Kazuma Nakano, Makiko Shimoji, Hinako Tamotsu, Noriko Ashimine, Shun Ohki, Misuzu Shinzato, Kuniko Teruya, Kazuhito Satou, and Takashi Hirano Okinawa Institute of Advanced Sciences, Uruma, Okinawa, Japan. Corresponding author. Akino Shiroma, Email: pj.ro.saio@amorihs.

S. aureus research on defense mechanisms:-
  1. Biofilm formation
  2. Adhesins
  3. Defensins

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Suggested additional resources and further reading 
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Classic eBook Collection:

Catalog of scientific papers, 1800-1900; Subject Index; Royal Society of London. Volume 19. Published in 1908 by University Press in Cambridge. 902 pages. Written in English.
  • Call number ABA-4714
  • Digitizing sponsor Internet Archive
  • Book contributor Gerstein - University of Toronto
  • Collection gerstein; toronto
Can download the PDF and other versions.

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Encyclopedia of Genetics, Genomics, Proteomics, and Informatics

NCBI = National Center for Biotechnology Information

DNA information
  • Nucleotide sequence accession numbers. 
The complete genome sequences of the S. aureus subsp. aureus DSM 20231T chromosome and plasmid were deposited in DDBJ/ENA/GenBank under the accession numbers CP011526 and CP011527, respectively.

Protein information

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Thursday 26 May 2016

Ingrown toe nail

Ingrown toenail is a big problem that crops up all of a sudden. It is painful and pus can collect beneath the toenail and surrounding tissues. The affected toe is swollen, red and inflamed. What can be done?

There is no need to panic. Look around you and try to find something that contains alcohol or menthol. It can be any of the oils that you use when you get hurt. For most of us, we have minyak Mastika or any minyak angin. That is fine. You can use that. But there is a better oil to keep at home and always have in your home collection of medicinal oils. This is the tea tree oil. It comes in small bottles, 25 ml. You can purchase it at Guardian Pharmacy. Keep it handy. The one that I keep and often use is Thursday Plantation Tea Tree Oil 25ml (100% pure essential oil), which is an Australian brand.


For ingrown toenail, pour a drop of tea tree oil onto the painful ingrown toenail. Do that at least once a day for 3 days until the pain subsides.

Muslims pray 5 times a day and wash their feet when performing ablution - the oil is washed away. Re-apply tea tree oil to the painful ingrown toenail after each prayer, for faster healing.
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