Shower Curtain
Description of Niche
Location of Niche
Organisms such as bacteria and fungus tend to thrive on the surface of shower curtains that face the water source.
Physical Conditions
A shower curtain will have a wide range of physical conditions depending on its location and usage. Typically the temperature and pH will be highly variable- changing with every use of the shower as well as its location on the globe- while pressure remains relatively constant at near atmospheric pressure and moisture/humidity, although not constant, are relatively high. There is a wide range of organic and non-organic material that organisms must make use of or protect themselves from such as dead skin cells, soil, other organisms introduced, detergents, cleaning solutions, and possibly blood, urine, and feces. Thus, we see that the organisms that live in this niche have a unique metabolism that allow them to break down many materials and have several defense mechanisms to shield themselves from products that threaten them.
Influence by Adjacent Communities (if any)
Is your niche close to another niche or influenced by another community of organisms?
Conditions under which the environment changes
Do any of the physical conditions change? Are there chemicals, other organisms, nutrients, etc. that might change the community of your niche.
Microbes That Live Here
Serratia marcescens is a motile, airborne, gram negative bacterium found naturally in soil, water, the subgingival biofilm of teeth, and sometimes in the intestines. In humans, it is a pathogen associated with a range of problems, including urinary tract infections, wound infections, conjunctivitis, keratitis, and meningitis. In bathrooms, it is commonly responsible for the red or pink slimy substance found on surfaces. S. marcescens prefers damp environments, and can grow in temperatures from 5 to 40°C and pHs from 5 to 9. It is notable for being able to perform casein-hydrolysis, which produces metalloproteases believed to function in extracellular matrix formation. Another distinction in its metabolism is its ability to break down tryptophan and citrate, and to convert the latter to a source of carbon. This fairly unique metabolism may serve as an advantage in communities. It is a facultative anaerobe, and can produce lactic acid by oxidative or fermentative metabolism. Only in recent history has S. marcescens been recognized as a human pathogen, and several strains are antibiotic-resistant. While chlorine is known to help control S. marcescens populations, the most effective disinfectant is bleach. (Harn)
Nocardia
Afipia felis
Moraxella osloensis (Kelley et. al 2004)
Methicillin Resistant Staphylococcus aureus (MRSA)
Escherichia coli (Barrett 2003)
Non-microbes Present
Aspergillus niger (Barrett 2003)
Phoma violacea (Green 1972)
Interaction of Microbes
The fungus known to grow in the shower curtain has several methods to compete with other organisms. For example, Aspergillus niger is able to produce the antibiotics malformin and tensyuic acids (Curtis et al and Yoko et al), as well and antifungal peptides (Gun et al).
Do the microbes change their environment?
Do they alter pH, attach to surfaces, secrete anything, etc. etc.
Do the microbes carry out any metabolism that affects their environment?
Do they ferment sugars to produce acid, break down large molecules, fix nitrogen, etc. etc.
The fungal species Phoma violacea is able to digest a variety of carbohydrates such as: glucose, mannose, galactose, sucrose, lactose, raffinose, xylose, rhamnose, mannitol, dextrin, starch; as well as a wide variety of fatty acids including: laurate, myristate, palmitate, stearate, linoleate, ricinoleate, "alkali-refined linseed oil"; and is vitamin-autotrophic (Eveleigh). Thus, they are well adapted to changing conditions of the shower because they are able to metabolize a wide range of materials and create molecules that are essential to them.
How to keep it clean
Antimicrobial Shower Curtain
Aegis™ Environments have developed antimicrobial materials that include shower curtains. This “Microbe Shield Technology” kills microbes without the use of harmful chemicals that are conventionally used. The compound 3-Trimethoxy silyl propyl dimethyl octadecyl ammonium chloride is responsible for its antimicrobial properties. There are three parts to this compound. First, the silane base is the anchor for this antimicrobial compound. It is covalently bound to the surface by hydrolysis reactions which allow crosslinking and polymerization to other molecules. Second, the centrally positively charged nitrogen draws the microbes (cell membrane is negatively charged.) Third, the long molecular chain (18) is responsible for piercing the microbe. As the microbes are drawn to the positively charged nitrogen, they are pierced. Electrocution also occurs due to the interaction of the positive nitrogen and the negative cell wall.
Disinfectant
bleach
clorine
Current Research
Hey, I found these while looking up other stuff: keep or discard at your discretion! :) -Harn
"http://technology.newscientist.com/article/dn11037-bacteria-harnessed-as-micro-propeller-motors.html" Sphingomonas used as miniature motors "In the future, such hybrid swimming micro-robots could even be used to deliver drugs inside the liquid environments of the human body, such as the urinary tract, eyeball cavity, ear and cerebrospinal fluid"
http://www.uwnews.org/article.asp?articleID=2030 Mapping Pseudomonas genome may help with cystic fibrosis "Scientists have completed mapping the genome of Pseudomonas aeruginosa, the largest bacterium sequenced so far, which may lead to potential new treatments for patients with cystic fibrosis (CF), patients with severe burns and others who develop this type of infection. The findings are reported in the Aug. 31 issue of the British journal Nature."
References
Barrett Tony D. International Journal of Therapy and Rehabilitation, Vol. 10, Iss. 6, 01 Jun 2003, pp 281
Curtis, Roy W., Walter R. Stevenson, and John Tuite. Malformin in Aspergillus niger-Infected Onion Bulbs (Allium cepa). Appl Microbiol. 1974 September; 28(3): 362–365.
Eveleigh, D. E. The growth requirements of Phoma violacea, with reference to its disfiguration of painted surfaces. Ann. appl. Biol. (1961), 49, 412-423.
Green W. F. Precipitins against a fungus, Phoma violacea, isolated from a mouldy shower curtain in sera from patients with suspected allergic interstitial pneumonitis. Med J Aust. 1972 Apr 1;1(14):696-8.
Gun Lee D, Shin SY, Maeng CY, Jin ZZ, Kim KL, Hahm KS. Isolation and characterization of a novel antifungal peptide from Aspergillus niger. Biochem Biophys Res Commun. 1999 Oct 5;263(3):646-51.
Yoko Hasegawa, Takashi Fukuda, Keiichi Hagimori, Hiroshi Tomoda and Satoshi Ōmura, “Tensyuic Acids, New Antibiotics Produced by Aspergillus niger FKI-2342”, Chem. Pharm. Bull., Vol. 55, 1338-1341 (2007).
edited by Mary De Unamuno, Christy Furukawa, Raymon Araniego, Harn Chiu, Coel Momita, and Delaram Rostami (students of Rachel Larsen)
