Detailed presentation on sex hormones in FUNGI

1. SEX HORMONES IN
FUNGI
BY: ANISHA KAZI
M.Sc SEM 1(MICROBIOLOGY)

2. SYNOPSIS:
 INTRODUCTION
 HISTORY
 CLASSIFICATION & TYPES OF HORMONES
 SIRENIN
 ANTHREDIOL
 OOGONIAL
 TRISPORIC ACID
 YEAST 𝛼 FACTOR
 CONCLUSION
 REFERENCES

3. INTRODUCTIO
N
 De Bary in 1881, first reported the presence of sex hormones in dioecious
species of Achyla.
 In 1908, Kaufmann supported De Bary on the basis of his observation on
Saprolegnia hypogyna. . According to him, the development of an
anthredial hyphae is stimulated by certain hormones.
 Hormones are the chemical substances that are produced in
one part of an organism & move to another part by diffusion,
where it can induce specific response.
 Sex hormones may be defined as the diffusible substance ,
playing a specific role in sexual reproduction.

4. HISTORY
 In 1881, first sex hormone was discovered by De Bary.
 In 1908,Kaufman supported De Bary’s theory on the basis of his observation.
 In 1924, Couch & in 1957 Bishop on Dictyuchus and Sapromyces reinschii
& Raper in 1954 have substantially confirmed the role of hormones in sexual
reproduction of fungi.
 In 1967, Van Den Ende defined the term hormone for fungi.
 In1972 ,Machilis classified the hormones.

5. CLASSIFICATION & TYPES OF
HORMONES
Machlis (1972) has classified the sex hormones into the following three types:
 Erotactins: attracts motile cells ("sperm attractant").
 Erotropins: includes chemotropic growth of sex organs.
 Erogens: controls the induction and differentiation of sex organs.
There is no evidence of existence of number of sex hormones in fungi,but few of
them are identified and chemically characterized such as Sirenin,
Anthrediol,Oogonial, Trisporic Acid & Yeast D Factor.

6. 1.SIRENIN
■ It is a sperm attracting hormone produced by water mould Allomyces, A.
macrogynous and A. arbuscula.
■ It is the female gametes which release sirenin to attract the male gametes.
■ The synthesis of sirenin by female gametes and their function to attract male
gametes was demonstrated by Machilis in 1958.
■ Sirenin is produced by both female gametangia & female gametes, which is
released into water. The male gametes under the influence of this hormone,
surrounds the female gameteangia.
■ Pairing of the male and female gametes results in the formation of dploid
motile zygotes.
■ Sirenin is active at very low concentrations (10-10 g ml-1 ),but it does not affect
the diploid gametes.

7. STRUCTURE OF SIRENIN :-
■ Nutting Rapoport and Machlis determined the structure of sirenin as a bicyclic
sesquiterpenediol and suggested its stereochemistry by analogy with the
corresponding hydrocorbon, sesquicarene.
■ Plattner and Rapoport (1971) synthesized d and l sirenin separately and
Machilis showed that l-sirenin attracted male gamete.
■ The empirical formula if sirenin is C15H24O2 and the
Molecular weight is 236.
■ It has been found that the l form of sirenin is more
biologically effective.

8. 2. ANTHREDIOL &
OOGONIAL
■ Raper (1939-1959), on the basis of his classical studies on sex hormones in Achlya,
demonstrated the presence of multi hormonal regulatory system in A. ambfsexualis
and A. bisexualis.
■ He envisaged the presence of four hormones A, B, C and D but now it has been
conclusively proved that only two hormones named as Antherldiol and oogoniol are
involved. Hormones A and C are antheridiols and hormones B and D are oogoniols.
Fig: Depecting sexual reproduction
in Achyla

9. ANTHREDIOL:-
■ Antheridiol is a crystalline compound having empirical formula as C2H42O5 and
molecular weight as 470. The hormone was isolated by Mc Morris and Barksdali
(1967) and its structure was proposed by Arsenault et al (1969).
■ It is a steroid hormone which is active at
concentration down to 10-10 M.

10. It is reported that Antheridiol stimulate four
types of reactions:
■ initiation of antheridial hyphae on male plant,
■ chemotropic stimulation of antheridial hyphae,
■ stimulation of male hyphae for production of oogoniol and
■ delimiation of antheridia.

11. OOGONIAL
:-
■ The hormone is synthesized by male hyphae of Achlya ambisexualis only in
the presence of antheridiol.
■ However, Barksdali et al. (1974) reported that Oogoniol is synthesised by some
hermaphrodite strains without the stimulus of antheridiol.
■ Two crystalline compounds, possessing hormone B activity have been isolated
from culture filtrates of Achlya heterosexualis by Mc Morris and his
coworkers (1975).
■ These have been named Oogoniol-1 &Oogoniol-2.

12. STRUCTURE OF OOGONIAL-
■ Oogoniol is a crystalline steroid with molecular weight as 500. The hormone
stimulates the development of oogonium on female hyphae.
■ The hormone stimulates the development of oogonium in female hyphae.

13. 3.TRISPORIC ACID
:-
■ Trisporic Acid is isolated from Blakeslea trispora and Mucor mucedo. It
has been found to play active role in sexual reproduction of several
members of the order Mucorales.
■ Though the concept of sex hormone in mucorales was developed in 1924
by Burgeff, it was only in 1956 that Burgeff could isolate a sex hormone in
cell free extract and this sex hormone was named as Trisporic Acid.
■ It is an unsaturated and oxygenated form of trimethyl cyclo- hexane.
■ For a long time, this acid was known as a metabolite associated with
carotenogenesis.

14. STRUCTURE OF TRISPORIC ACID:-
■ Three kinds of trisporic acid have been identified:
Trisporic acid A, B & C.
 Trisporic acid C plays the major role (80 %) activity
 Trisporic acid B with 15% activity
 & Trisporic acid A is least active with (1-2%) activity.
■ Empirical formula of trisporic acid is C18 H26 O4
& the molecular weight is 306.

15. PRODUCTION OF TRISPORIC ACID
■ The role of sex hormones in Mucor mucedo was studied by
Plempel et al. (1957-61). It is synthesized from 𝛽-carotene.
■ In the heterothallic mycelia, trisporic acid B and C stimulate the
development of zygophores. This hormone is synthesized only when the
mycelia of (+) and (-) strains grow in a normal continuous diffusable
medium.
■ The hormone trisporic acid synthesized in (-) strain induces the
development of progametangium in (-) strains and vice-versa.
■ The zygophores of (+) and (-) strain are attracted towards each other due
to chemotropic response of a volatile substance which also promotes the
synthesis of trisporic acid in two opposite mating types.

17. 5. YEAST 𝜶 𝐅𝐀𝐂𝐓𝐎𝐑
 The presence and the involvement of some hormone in the sexual reproduction
of Saccharomyces cerevisiae was suggested by Levi in 1950.
■ The haploid cells are of two mating types a &𝛼 which conjugate to form diploid
cells.
■ In 1956, Levi showed that the 𝛼 haploid cells produce a diffusible chemical
which induces the formation of copulatory process by compatible a cells.
 These a cells, due to influence of the chemical substance produced by o cells,
stop their growth and reproduction by budding.
■ Instead, these a cells swell in size and form giant cells of various shapes. These
giant cells are 30 or more times heavy in dry weight in comparison to normal
haploid cells. The 𝛼 factor acts only on a cells and has no effect on 𝛼 cell.
■ The 𝛼 factor is reported to inhibit DNA replication in the a cells. Duntze (1970
— 1973) isolated the a factor in pure form. It is peptide complexed with copper
ion and has molecular weight of 1400.

18. CONCLUSION
:
Chemical substance that is produced in one portion of an organism and moves
by diffusion or transport to another portion of same individual or to other
individual of same species where it induce specific response is called hormone.
 Fungal sex hormones are produced in very small quantity.
 Hormones play specific role in sexual reproduction in fungi.

19. REFERENCES :-
■ Botany-Fungi Vashista B.R. & Sinha.
■ Textbook of Microbiology R.P. Singh.
■ Textbook of Microbiology Dubey & Maheshwari.
■ General Microbiology:Stainer ,Ingrahamana.

20. THANK YOU.