ECOLOGÍA MICROBIANA Dr. Arturo Massol Deyá

Universal Phylogenetic Tree based on rRNA sequences

From: Woese (2000) PNAS 97:8392-8396.

micro-organisms: largest diversity, mostly unknown

2 species: <70% similar

multicellular, macroscopic organisms: small branches in the Eucarya-domain:

Homo sapiens -chimpansee: 98.4% similar!

Antony van Leeuwenhoek (1677) Philosophical Transactions of the Royal Society of London 11(133):821-831 [Oct 9, 1677].!

“…the same day at night, about 11 a clock, I discovered some few living creatures: but the 3d of June I observed many more which were very small, but 2 or 3 times as broad as long. This water rose in bubbles, like fermenting beer”.!

Philosophical Transactions of the Royal Society of London 14(159):568-574 [May 20, 1684].!

“…tho my teeth are keep usually very clean, nevertheless when I view them in a magnifying glass, I find growing between them little white matter as thick as wetted flower: in this substance tho I do not perceive any motion, I judged there might probably be living Creatures”.!

The Discovery of Microorganisms Revisited: A close reading of 17th-century documents shows that Hooke, rather than Leeuwenhoek, was the first to observe a microorganism.

Howard Gest ASM News. 2004. 70(6):269

Ortus Medicinae, 1667 Johann B. van Helmont (médico holandés)

...Las criaturas tales como los piojos, garrapatas, pulgas y gusanos son nuestros miserables huéspedes y vecinos, pero nacen de nuestras entrañas y excrementos. Porque si colocamos ropa interior llena de sudor con trigo en un recipiente de boca ancha, al cabo de veintiún días el olor cambia y el fermento, surgiendo de la ropa interior y penetrando a través de las cáscaras de trigo cambia de trigo en ratones. Pero lo que es más notable aún es que se forman ratones de ambos sexos, y que éstos se pueden cruzar con ratones que hayan nacido de manera normal...Pero lo que es verdaderamente increíble es que los ratones que han surgido del trigo y la ropa íntima sudada no son pequeñitos, ni deformes ni defectuosos, ¡sino que son adultos perfectos!

Experimentos de van Helmont.

Experimentos de Francesco Redi (médico; aprox. 1668)

 Spallanzani  Pasteur  Koch  Darwin (1859)

…ecología microbiana

 Sergei Winogradsky (1856-1953) •  Ruso •  Bacterias fototrofas (anaerobias) •  Bacterias oxidadoras de hierro y azufre

(quimiolitotrofía; autotrofía, ej. Beggiatoa) •  Describió bacterias anaerobias fijadoras de

nitrógeno •  Fundador de la Microbiología de Suelos

…ecología microbiana  Martinus Beijerinck (1851-1931)

•  Botánico Holandés •  Técnica de enriquecimiento para aislar

microorganismos (aislación selectiva) •  Cultivó bacterias de suelo y ambientes acuáticos

como bacterias aerobias fijadoras de nitrógeno, bacterias reductoras de azufre (anaerobias), bacterias oxidadoras de azufre (aerobias), bacterias simbióticas fijadoras de nitrógeno, Lactobacillus sp., algas verdes y muchos otros.

•  Bacterias y su rol en el ciclo de N y S •  Fundador de la Ecología Microbiana

Alexander Fleming (1929)!

Journal of Experimental Pathology 10:226-236.!

“While working with Staphylococcus variants a number of culture-plates were set aside on the laboratory bench and examined from time to time. In the examinations these plates were necessarily exposed to the air and they became contaminated with various micro-organisms. It was noticed that around a large colony of a contaminating mould the staphylococcus colonies became transparent and were obviously undergoing lysis”.!

Milestones in Microbiology: 1546 to 1940 (Edited Thomas Brock 1961).!

Fuentes de Información

Internet:

 http://cme.msu.edu/  http://microbes.org/  http://www.asm.org/  http://www.ncbi.nlm.nih.gov/PubMed/

Revistas

 Microbial Ecology  ASM journals (AEM, JB, etc.)  Otros

Récord Fósil

Oparin

Miller

Chun Kuxtal

LOS COMPONENTES PRINCIPALES DE AIRELIMPIO Y SECO

Gas Fórmula Volumenen aire (%)

NitrógenoOxígenoArgón

Dióxido de carbonoNeónHelio

MetanoCriptón

HidrógenoOxido nitroso

N2O2Ar

CO2NeHeCH4KrH2

H2O

78.0820.940.9340.035

0.001820.000520.000150.000110.000050.00005

Comparison of atmospheric and temperature conditions (Lovelock, 1979).!

Atmosphere Mars VenusEarth

withoutlife

Earthwith life

CO2N2O2

95%2.7%0.13%

98%1.9%trace

98%1.9%trace

0.03%79%21%

SurfaceT (°C) -53 477 250 ± 50 13

Major carbon reservoirs (Bolin et al., 1979).!

Reservoir Amount (billions of metrictons of carbon)

Atmosphere before 1850Atmosphere in 1978Oceans and fresh water

inorganicDissolved organicLand biotaSoil organic matterSedimentsFossil fuels

560-610692

35,0001,000

600-9001,500

10,000,00010,000

Biodiversidad (vocabulario)

 Formas Ancestrales  Extinción  Especiación  Adaptación  Selección Natural  Evolución

bioDIVERSIDAD

Prokariotas vs. Eucariotas

Dirk Schüler/Archieves of Microbiology (2004) 181:1-7 (MINI-REVIEW)

Molecular analysis of a subcellular compartment: the magnetosome membrane in Magnetospirillum gryphiswaldense