Ponencia: Introduction to endophytes and their application to develop commercial products
Autor: Dr. Gary Strobel
Evento TF Innova: Workshop Biotechnology "Isolation and identification of endophytic fungi from vascular plants"
19. Ipecac Products from the
Rainforest
Taxol
Vinblastine
Reserpine
Tubocurarine
20. Definition of An Endophyte
By definition an endophyte is a
microorganism that becomes
established in a higher
plant and does not cause any
overt symptoms or cause any
apparent tissue damage
22. Areas of High Plant Biodiversity
70-80% of the Earth’s Plant Diversity Occurs on 1.5% of Its Land
Area
Is this also true of microbial diversity?
23. ant Diversity in the Canary Isles
0 million year old landscape..
About 2000 plant species
About 528 of these are endemic
Chances of finding novel endophytes
are great
24. Selecting Plants for the Isolation of
Endophytes
1. Visiting Areas of High Plant Biodiversity
2. Finding Gondwanaland Plants
3.Meeting and Learning from Native Peoples
25. Progress on Endophytic Microbes
Examples of products-jesterone, hydroxyjesterone
pestacin, isopestacin, ambuic acid, ecomycin, oocydin A
munumbicins, kakadumycin, cryptocandin, pseudomycins
and others.
Ambuic Acid: JOC (2003) 4609-4614
26. A Bastion of Biodiversity-the
World’s Rainforests
36. Tripterigeum
wilfordii a Chinese
medicinal plant used
to treat arthritis
and other ailments
of the joints and
limbs possesses a
plethora of
endophytic microbes
including
Cryptosporiopsis
quercina.
41. Biological Activity of Cryptocandin
Test Fungal MIC MIC of
Pathogen micrograms/ml Amphotericin B
of Cryptocandin
Candida albicans 0.03 0.03
Cryptococcus > 20.0 0.04
neoformans
Aspergillus >20.0 0.03
fumigatus
Histoplasma 0.01 0.01
capsulatum
58. Some Characteristics of Isolate P-25
1. Is endophytic on Monstera speciosa
2. Appears to be a streptomycete
a. Only bacterial primers function
to give product from its ribosomal DNA
b. Primers for 18Sr DNA do not function
c. Has no discernable nucleus (by nuclear staining)
d. Gram positive
3. Has 16S r DNA sequences that have 95% similarity
to Streptoverticillum sp.
4. Makes Coronamycins
4. Has some characteristics of
Penicillum sp. but origin of spores is unique
5. Is not inhibited by cyclohexamide up to (or
greater) than 100 ppm
61. Properties of Coronamycins
1.Peptides- 2 principle ones MW.’s 1217
and 1203
2. Composition x:x methionine:tyrosine
and leucine-ratio-- 2:2:1:1:3
3. Active against pythicaeous fungi (2-16
micrograms/ml) ,and Cryptococcus
neoformans.
4. Extremely active against Plasmodium
falciparum IC 50 <1 ng /ml
69. Rainforest Microbiology- The Prospects and
Promises
1. Each individual plant has one or more associated
microorganisms. Only a few microbes have ever been
studied.
2. The relationships of the plant to the microbe may range
from symbiotic to weakly pathogenic.
3. Host specificity may exist with certain microbes which
places a huge emphasis on the preservation of the world’s
rainforests.
4. Products from endophytes have a wide range of uses in
medicine, agriculture and industry.
5. Peculiar microbes are plentiful and usually are to be found in
areas of high biodiversity.
6. The biology of endophytes is largely unknown.