Environmental Engineering Reference
In-Depth Information
be valuable in bacterial diversity studies since a
single array can contain thousands of DNA se-
quences (De Santis et al.
2007
) with high speci-
ficity. Specific target genes coding for enzymes
such as nitrogenase, nitrate reductase, naphtha-
lene dioxygenase, etc., can be used in microarray
to elucidate functional diversity information of
a community. Sample of environmental “stan-
dards” (DNA fragments with less than 70 % hy-
bridization) representing different species likely
to be found in any environment can also be used
in microarray (Greene and Voordouw
2003
).
There are some other molecular methods that
have been used potentially to study the micro-
bial community. Fluorescent in situ hybridiza-
tion (FISH) (Dokić et al.
2010
), DNA sequencing
based community analysis such as pyrosequenc-
ing based community analysis (Fakruddin and
Chaudhary
2012
), illumina-based high through-
put microbial community analysis (Degnan and
Ochman,
2012
) etc. are some examples for these
techniques. Most of these methods are not as ap-
propriate as previously mentioned methods.
Viruses in marine samples can be studied by
nonmolecular methods: transmission electron
microscopy (TEM) and epifluorescent micros-
copy (DAPI stain) by differential filtration. The
development of improved methods for isolating
and characterizing virus in the marine environ-
ment now makes it possible to study their role in
ecosystem (Table
4.1
).
World Conservation Monitoring Center has
described 1,604,000 species at the global level.
India accounts for 8 % of global biodiversity ex-
isting in only 2.4 % land area of the world. Mi-
crobial diversity conservation requires certain
specialized techniques for applications in recla-
mation of a tainted habitat. Both ex situ and in
situ techniques can be employed to preserve the
biodiversity.
4.7.1
Ex Situ Preservation
The most effective and efficient mechanism for
conserving biodiversity is to prevent the destruc-
tion or degradation of the habitat. Because of
the uncertainties associated with in situ conser-
vation of microorganisms, ex situ preservation
plays a major role in microbiology and includes
the gene banks, culture collections, and micro-
bial resource centers forming the repository for
microbial isolates and do away with need for
costly and time consuming reisolation protocols.
The CBD encourages adoption of measures for
ex situ conservation of biodiversity, preferably
in the country of origin. Application of this ap-
proach is supported by the World Federation for
Culture Collection (WFCC) and Directory of
Collection of Cultures of Microorganisms. More-
over, four other associations that directed toward
this effort are Oceanic and Atmospheric Admin-
istration for marine microbial diversity, National
Institute of Health for deciphering the emerging
microbial pathogen diversity, American Society
for Microbiology, and American Phytopathologi-
cal Society.
In India, this work has been carried out by
the Ministry of Environment and Forests and
the Ministry of Science and Technology that in-
cludes various departments such as the Depart-
ment of Agriculture Research and Education,
Indian Council of Forestry Research and Educa-
tion, Department of Biotechnology. The level of
the microbial type culture collection section of
IMTECH, Chandigarh has now been upgraded
to an International Depository Authority (IDA)
and it involves the culture collection and main-
tenance as well as distribution of pure cultures
4.7
Conservation of Microbial
Diversity
The problem of biodiversity is essentially one of
conflict resolution between the human kind on
one side and living organisms inhabiting differ-
ent environment on the other side. The UNCED
(United Nations Conference on Environment and
Development) process has helped place the loss
of biodiversity and its conservation on global
agenda. The Convention on Biological Diversity
(CBD) that emerged from the UNCED or Earth
Summit at Rio de Janerio in June 1992 is now a
treaty.
Search WWH ::
Custom Search