Talk:Bacterial lawn

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What's the scale of the pic? I can't tell if it's 1mm, 1cm or 1m across... Stan 20:39 10 Jun 2003 (UTC)

The longest raised mat area is a little over half a metre long. --mav
Ah. But clearly my question is too subtle of a hint :-) - could we please get a caption so readers know exactly what they're looking at? If this is one of those mega-mats in Yellowstone, let's say so. At first I thought it was an angled closeup of a petri dish. Stan 21:55 10 Jun 2003 (UTC)
Done. --mav


Is there a distinction between a bacterial lawn and a biofilm? My understanding of biofilm is that it is bacteria that form a community that has a complex multicellular structure. They cooperate and have differentiated roles - division of behavior much like a multicellular organism. They exchange molecular signals to coordinate behavior. --huddy

[biofilm primer]

I was wondering the same thing when reading the article. I don't know too much about bacterial lawns, so I can't say for sure that they are different. But I agree that a biofilm usually has multiple species of bacteria and archaea interacting in complex ways through biochemical signals and physical connections. This leads to much heterogeneity on all scales. Bacterial lawn seems to describe overlapping clonal colonies (i.e. each grown from a single cell own a petri dish) but with no real integration or structure implied.
The other distinction I've seen is that biofilms usually form on solid/liquid boundaries (e.g. enamel/saliva in a tooth, metal/water in a pipe, rock/water in a stream...) while bacterial lawns tend to be found on solid/gass boundaries (e.g. petri dish/atmosphere). Also biofilms have some kind of extra-cellular matrix to protect them and hold them together. I don't think this is a requirement of lawns.
I tend to think of them as separate ideas, although there is some minimal overlap. But I couldn't argue much against a view that considered biofilms to be a special case of bacterial lawns. --jmeppley
OK, I've done it. There are now 2 articles. I tried to incorporate all the existing text into one of the 2 pages. The Bacterial Lawn page is now basically a stub and the new Biofilm page doesn't read as well as I 'd like, but I think its an improvement. All the referencing pages seemed to refer to the correct redirect page, so I didn't change any links. Jmeppley 21:21, 7 Sep 2004 (UTC)

removed sentence[edit]

I just removed the sentence:

These regions are common on deep-sea floors, especially near hydrothermal vents.

I just edited the article to clarify that usual usage of bacterial lawn refers to conditions that generally only happen in the laboratory. (nutrient rich with no competition or threat or physical stress). Any bacterial (or archaeal) aggregations in the deep sea are going to be biofilms. Jmeppley 18:24, 27 October 2005 (UTC)[reply]

Lawn Culture[edit]

I think what the original author meant was "Lawn Culture", a lawn culture is a microbiological technique of inoculating bacteria on media plates, so that after incubation there is an even culture of bacteria on the plate with no gaps. It's often used to determine antibiotic resistance or susceptibility. This is done by making a lawn culture, then placing an antibiotic disc on the media. Zones of Inhibition (no growth) are formed around the discs if the organism is susceptible to the antibiotic.

The sentence from the article "when all the individual colonies on a petri-dish agar plate merge together to form a field or mat of bacteria." to describe a bacterial lawn is misleading. The use of merge together implies the bacteria have "swarmed" across the plate, with only occurs with highly motile bacteria such as Pseudomonas aeruginosa Proteus mirabilis. They don't merge together, it is simply that the individual bacteria are spread evenly across the plate so when colony formation occurs the colonies touch each other at the edges. (Yes they merge but not in the way a microbiologist would consider it)

I'm not comfortable enough with editing wiki to remove an entire text and replace by what I think was meant, but I hope this information helps someone who is. Also I have never heard of the term "bacterial lawn" as being interchangable with the term "biofilm", they are simply not the same. Jessica87au (talk) 02:38, 11 April 2008 (UTC)[reply]