Transcript Industrial Microorganisms Industrial Microorganisms The laws of applied microbiology (David Perlman, 1980) • The microorganism is always right ( your friend, a sensitive partner). • There.

Industrial Microorganisms
Industrial Microorganisms
The laws of applied microbiology (David Perlman,
1980)
• The microorganism is always right ( your friend, a
sensitive partner).
• There are no stupid microorganisms.
• Microorganisms can (will) do anything.
• Microorganisms are smarter (wiser, more
energetic) than chemists, engineers, etc.
• If you take care of your microbial friends, they
will take care of your future (and you will live
happily ever after).
Microorganisms are useful to provide
products & services
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Ease of mass cultivation
Speed of growth
Use of cheap substrates (wastes)
Diversity of potential products
Ability to readily undergo genetic manipulation
Believes of industrial microbiologists
• The biochemical capabilities of microorganisms
are vast.
• A wide variety of new or unusual substances may
be produced by various microbial isolates. Of the
10,000 antibiotically active compounds known in
the late 1980's, 67% are produced by
microorganisms (67% by actinomycetes, 9% by
other bacteria, and 15% by fungi).
• No door will always be locked . The key is to
develop smart procedure and work efficiently. The
capacity of an industrial screening group for
isolation of microorganisms and thorough testing
is around 1000 - 2000 strains per year.
Microbial genera with established
industrial roles - 1
• Archaeans: Methanobacterium, Methanococcus,
Pyrococcus, Sulfolobus
• Gram-negative bacteria: Acetobacter, Acinetobacter,
Agrobacterium, Alcaligenes, Azotobacter, Erwinia,
Escherichia, Klebsiella, Methylococcus, Methylophilus,
Pseudomonas, Ralstonia, Salmonella, Sphinggomonas,
Spirulina, Thermus, Thiobacillus, Xanthomonas, Zoogloea,
Zymomonas
• Gram-positive bacteria: Actinomyces, Actinoplanes,
Arthrobacter, Bacillus, Brevibacterium, Clostridium,
Corynebacterium, Lactobacillus, Lactococcus,
Leuconostoc, Micrococcus, Mycobacterium, Nocardia,
Propionibacterium, Streptococcus, Streptomyces
Microbial genera with established
industrial roles - 2
• Filamentous fungi: Acremonium, Agaricus,
Aureobasidium, Aspergillus, Claviceps, Coniothyrium,
Curvularia, Cylindrocarpon, Fusarium, Lentinus,
Mortierella, Mucor, Paecilomyces, Penicillium,
Rhizomucor, Rhizopus, Sclerotium, Trametes, Trichoderma,
Trichosporon
• Yeasts: Blakeslea, Candida, Hansenula, Kluyveromyces,
Pachysolen, Phaffia, Pichia, Rhodotorula, Saccharomyces,
Xanthophyllomyces, Yarrowia, Zygosaccharomyces
Requisites of an industrial
microorganism - 1
• Stability: available in pure culture; genetically
stable; possible to be maintained for a long period
of time; give a predictable amount of desired
product in a given fermentation time
• Cultivation: grow in large-scale; produce many
vegetative cells, spores, or other reproductive units;
grow vigorously and rapidly in the preparation of
inoculum
• Safety: not be harmful to humans or economically
important animals or plants; not produce toxic
substances. GRAS (generally regard as safe)
microorganisms; crippled strains of GMMs
(genetically manipulated microorganisms) or
pathogens
Requisites of an industrial
microorganism - 2
• Economics: grow in inexpensive culture medium
obtainable in bulk quantities (wide range of cheap
carbon sources, limited or no need for growth
factors); produce the required product within a
short period of time (preferably in 3 days or less);
protect itself against contamination, e.g. lowering
the pH, growing at high temperature, rapidly
elaborating microbial inhibitor; removed from the
culture medium easily; desired product is easily
separated from all others (e.g. ready breakage,
produce limited byproducts)
• Modification: amenable to genetic manipulation;
capable of genetic recombination; well
characterized route of biosynthesis
Examples of microorganisms classified
as GRAS (generally regarded as safe)
• Bacteria: Bacillus subtilis, Lactobacillus
bulgaricus, Lactococcus lactis, Leuconostoc oenos
• Yeasts: Candida utilis, Kluyveromyces marxianus,
Kluyveromyces lactis, Saccharomyces cerevisiae
• Filamentous fungi: Aspergillus niger, Aspergillus
oryzae, Mucor javanicus (Mucor circinelloides f.
circinelloides), Penicillum roqueforti
• Normally, these microorganisms require no further
testing if used under acceptable cultivation
conditions
Ref: Waites et. al., 2001
Approaches for obtaining new microbial
metabolites
• Screening: new isolates and/or new test methods.
• Chemical modification: microbial substances.
• Biotransformation: microbial or enzymatic
reaction.
• Interspecific protoplast fusion: new or hybrid
substances are expected, widely used in the
antibiotic industry.
• Gene cloning: genes of producers of known
substances; transfer of genes to nonproducers
which contain "silent" genes, leading to the
generation of modified or even new substances.
References
• David Perlman, 1980
• Waites, M. J., N. L. Morgan, J. S. Rockey, and G.
Higton. 2001. Industrial Microbiology: An
Introduction. Blackwell Science Ltd
問題
• 與動、植物相比，利用微生物生產有用產品，
具備哪些優勢？
•好的工業生產用微生物菌株應具備哪些條件？
• 常見的GRAS菌種有哪些用途？
• 下列名詞的內涵？ GRAS, GMMs, protoplast
fusion