From: wastec@unpsun1.cc.unp.ac.za (Centre For Waste Technology)
Newsgroups: bionet.general
Subject: RE: INFORMATION ON MSc PROJECT
Date: 7 Jan 93 13:33:42 GMT
Distribution: bionet
Original-To: bioforum@uk.ac.daresbury
X-Mailer: ELM [version 2.3 PL11]

Greetings great, wide world,

REQUEST FOR INFORMATION ON IMAGE ANALYSIS AND BIOFILM FORMATION.

Below is a summary of what I am doing for my
"MASTERS OF THE UNIVERSE and other small and insignificant
things......" theis. 

If anyone has any information they think could help me I would really
appreciate it.  Thank you in advance.

      To date, possibly due to methodological difficulties, no
definitive studies of the role of surfaces in soil have been
reported despite the fact that knowledge of this is central to
the understanding of the importance of microorganisms to, for
example, revegetation of landfill sites or in bioremediation.

     The central aim of this project is to establish
methodologies appropriate for definitive fundamental studies in
microecophsiology.  Development of sampling techniques,
microscopy and image analysis hardware and software, to determine
the behaviour of both planktonic and surface-attached (biofilm
forming) microorganisms in microecophysiological terms is central
to the study.  The first step is to establish methods for
studying the "real time" processes (of both individual microbial
and associations) of attachment, establishment, division and
growth on surfaces in situ, under constant, standardised
conditions.  The second step will be to modify these methods for
the study of microbial associations in situ.
 
      These methods will then be used to investigate the effects
of landfill leachate on soil during vertical migration and the
bioremediation of contaminated soil, which are two on-going
research programmes in the International Centre for Waste
Technology (Africa), University of Natal, Pietermaritzburg. 
Preliminary work has shown that two distinct microbial
populations, growth rate independent (surface-attached) and
growth rate dependent (planktonic) are significantly involved in
the processes.  Unfortunately, at present, there is no direct
method available to determine the rate of growth and significance
of the former population type and, thus, research progress has
been restricted.

     In order to reduce the considerable number of variables that
influence growth on surfaces, single associations will be used,
growing in defined, controlled conditions of continuous culture
microscopy units (CCMU) which are housed in a controlled
environment incubator which has sections for anaerobic and
aerobic environments.  The strictly controlled environmental
variables are temperature (30oC), substrate concentration, flow
rate, pH, light intensity and oxygen partial pressure.  The plan
is to set-up the CCMU, prior to inoculation and, subsequently,
monitoring of the growth of the associations.

     The analytical system consists of a microscope attached to a
video camera which allows images of selected microorganisms to be
stored for later analysis on a Vidas (Kontron) digital image
analysis system.  Images of morphologically distinguished
microorganisms can be measured at preselected times and the
values obtained used to accurately determine the growth rates of
the species.

     Any suggestions on the topics I have mentioned would be greatly
     appreciated, no matter insignificant they might seem.

Thanx in advance.

Yours sincerely
Barry Dudley

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BARRY DUDLEY
THE MASTERS OF THE UNIVERSE AND OTHER SMALL AND INSIGNIFICANT
THINGS.......................................................
International Centre for Waste Technology
Department of Microbiology and Plant Pathology
University of Natal
PO Box 375
Pietermaritzburg
3200
South Africa
Email wastec@unpsun1.cc.unp.ac.za

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