Department of Biotechnology, University of the Western Cape BTY227

1
Department of Biotechnology, University of the
Western CapeBTY227

• Molecular and Environmental Microbiology

2
Lecture 1.

• Module Introduction and Information
• Overview of molecular microbiology
• Review of nucleic acids and genomes

3
Module details are available on the departmental
web site

• http//www.biotechnology.uwc.ac.za/teaching/BTY227
  /

4
Your teachers

• Professor Don Cowan Module Coordinator
• Dr Heide Goodman Lecturer, Tutor and
• Practical Coordinator
• Dr William Stafford Lecturer and Tutor
• Mr Clifford Jacobs Practical Supervisor

5
Course Assessment

• Tests (2 x 50 minute short-answer) 20
• Practicals (6)
  30
• Written Exercise (1)
  10
• End of module examination (1.5h) 40

6
Course Texts

• Prescott et al. (1990) Microbiology, WCB Publ.
• A good introductory text, suitable for the
  module.
• Brock Madigan (2000) Microbiology
• An excellent microbiology text, covering the
  module (and more) very effectively.

7
Practicals

• Mondays, Term 4, in Micro Undergraduate Lab,
  1200h 1600h
• See laboratory Manual for details

8
Practical details.

• Lab reports are to be written up on a weekly
  basis. At each practical, you should hand in your
  write-up to the Demonstrator for marking.
• Lab reports handed in late will be subject to a
  mark penalty of 20 per week.
• Attendance at practical classes and submission of
  experimental write-ups are essential
  pre-requisites for passing this module.
  Attendance in practicals will be monitored.

9
Written Exercise

• You will be given a copy of a research paper, and
  a list of questions to answer.
• The answers to the questions will refer to the
  material in the paper, but may also require
  background reading.
• Reading Prescott Brock
• Plagiarism (copying/downloading etc) of written
  material will not be tolerated.
• Hand-written essays will not be accepted.
• A penalty of 10 per day will apply to late
  submissions.

10
Overview

• Microbes in the environment
• Microbes (bacteria, archaea, fungi, yeasts)
  inhabit virtually every niche available on this
  planet.
• A single gram of garden soil contains
  gt100,000,000 microbial cells, of 100 1000
  different species.
• Approx. 100,000 species are known (have been
  cultured and identified).
• True species diversity is estimated to be greater
  than 107.
• Microorganisms are involved in all virtually all
  global processes (e.g., elemental cycling)
• Microorganisms play an vitally important role in
  Biotechnology (e.g., antibiotics, fermentation
  processes, expression hosts, bioremediation).

11
Nucleic acids the molecules of life
DNA (deoxyribose nucleic acid)
Transcription
Replication mRNA (ribose nucleic acid)
Translation Protein Cell structure,
catalytic processes (enzymes), transport and
recognition (receptors), etc.
12
Structure of nucleic acid backbone
5-hydroxyl
5
4
1
2
3
3-hydroxyl
-H in DNA, -OH in RNA
Phosphodiester bond
Exist as right-handed double helices (DNA) or
single stranded RNA. The helix is stabilised by
base-pairing (GC) and (AT).
Reading Prescott, page 193
13
Super-structure of DNA
Bases Guanine Adenine Thymine
Cytosine Codons Triplets of
nucleotides encode specific
amino acids or expression signals.
E.g., ATG
Start/Met GCC Ala TGA Stop Genes
Open reading frames (coding sequences
flanked by translation
start and stop codons) which
encode proteins. Often around 1000
bp. Operons One or more ORFs flanked by
regulatory
sequences (promoter, operator, regulator). Genom
e The total complement of DNA in a
cell in bacteria typically
between 0.8Mb and 10Mb, and
containing around 104 ORFs.
Reading Prescott, pages 331-335 and 221-225