Essays - by Stephen G. Saupe, Ph.D.; Biology Department, College of St. Benedict/St. John's University, Collegeville, MN 56321; ssaupe@csbsju.edu; http://www.employees.csbsju.edu/ssaupe/
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Essays - by Stephen G. Saupe, Ph.D.; Biology Department, College of St. Benedict/St. John's University, Collegeville, MN 56321; ssaupe@csbsju.edu; http://www.employees.csbsju.edu/ssaupe/ |
The Biology of Resurrection: Life After Death in Fungi
(these are the notes from a seminar
that I have presented)
I.
What?
Cryptobiosis - �hidden or latent life�; i.e., anhydrobiosis � able
to withstand desiccation (other terms - abiosis, anabiosis)
II. Who?
Spores/sclerotia of fungi
rotifers
nematodes
tardigrades
Baker�s yeast
brine shrimp cysts (love those sea monkeys)
seeds
bacterial spores
III. How Long?
10,000+ years (seeds)
120 yr. (tardigrade)
52.5 yr. (Schizophyllum commune)
IV. Since when? (a brief history)
| 1702 | Antony von Leeuwenhoek | 70 years old; �animacules� from roof sediments |
| 1743 | John Tuberville Needham | Jesuit; eel worms (nematodes) in blighted wheat galls |
| 1753 | Henry Baker | confirmed Needham; �Life may be suspended and seeming destroyed�and yet, after a long while, Life may begin anew�� |
| 1769 | Lazzaro Spallanzani | �no way Needham!� (no experiments) |
| 1769 | Needham | recants � wimp |
| 1776/95 | D. Maurice Roffredi/Felice Fontana | confirm Needham�s work on eel worms, chastise wimpy Needham |
| 1776/03 | Spallanzani | �oops, sorry!� performed experiments on the stability of desiccated state; �privileged by nature, so to enjoy real resurrection after death� |
| 1823 | Francis Bauer | more eel worms (worked @ Kew with Sir Joseph Banks) |
| 1838 | Christian Gottfried Ehrenberg | life slowed, opponent of resurrection; erroneously suggested rotifers could thrive in dry sand |
| 1842 | Louis Doyere | studied resistance of desiccated state; suggested molecular arrangement endowed with potential for life |
| 1858/9 | Doyere vs FA Pouchet | Resurrectionist (Doyere) vs Anti-resurectionist (Pouchet) - major controversy/debate (parallel to spontaneous generation arguments) |
| 1859 | C. Darwin | Origin of Species � no big deal! (at least related to this issue) |
| 1859 | P. Broca & Commission of Biological Society of France | settled debate, sided with Doyere, but stopped short of saying all life stopped. Was the Church a factor as Broca speculated? Not. |
| 1960�s | James Clegg, John & Lois Crowe, et al | physiological/biochemical investigations with brine shrimp & nematodes |
| 1978 | Saupe | isolates trehalose from Marasmius oreades (revives upon drying); No big deal!? |
| 1985 | Saupe | finally wakes up! |
V. How do they do it?
Survival correlated with the synthesis and accumulation of
carbohydrates, such as trehalose and glycerol, during desiccation.
Trehalose
= 1- a
- D- Glucopyranosyl - a
- D- glucopyranoside
structure not inserted
VI. How does trehalose work? A model: not inserted
VII. Do Higher fungi resurrect? Yes!
Schizophyllum commune 45 years (Bixby), 52.5 years (Ainsworth)
Marasmius oreades revives
Fries (1835) � genus concept; difficult to determine (see table)
| Table: Generic Features for Marasmius & Collybia according to Fries (1835) | ||
| Feature | Marasmius | Collybia |
| Spores | white | white |
| Stipe texture | cartilaginous | cartilaginous |
| Revive? | yes | no |
VIII. Does Marasmius oreades revive?
M. oreades shows respiratory activity after reviving
Evidence: tetrazolium chloride staining, respirometry
Could it be bacterial or non-metabolic? Doubtful but not proven
IX. Is trehalose involved? - In yeast � YES!
Hi levels of trehalose (10-18%)
Trehalose correlated with the gassing ability of yeast
Yeast mutants without trehalose don�t revive
Trehalose increases during drying
Trehalase levels increase upon breaking
dormancy
X. Is trehalose involved in other fungi? Maybe
Widespread distribution in fungi
No clear correlation between trehalose content and revival ability
Then, why so much trehalose?
XI. Can
any specimen revive?
Screening program show few over about 2 years dry (in air), none older 5 yr.
XII. Philosophical Implications
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Life is nothing more, nothing less than the arrangement of certain molecules. B. Rensberger. Science 80 (Nov) |
Only when the structure is damaged or destroyed does the organism pass from the state of anabiosis...to that of death. D. Keilin (1959) |
XIII. Ecological Implications
Life span
Ephemeral environments
Seasonality (persist in unfavorable environments)
XIV.
Who cares?
Preservation of biological materials (i.e., blood, food)
Pathogens of plants/animals
Hypothermia
Panspermia?
References: (further reading)
Crowe, JH & JS Clegg. 1973. Anhydrobiosis. Dowden, Hutchinson & Ross, Stroudsberg, PA.
Keilin, D. 1959. The problem of anabiosis. Proc. Roy. Soc. London B 150:149-191.
Leopld, Carl. 1979. Membranes, Metabolism and Dry Organisms. Comstock.
Rensberger, B. 1980. Life in limbo. Science80. Pp 36-43. November.
Young, Stephen. 1985. The dry life. New Scientist. 31 October.
Weisburd, Stefi. 1988. Death defying dehydration. Science News 133: 107-110.