Bergey's Manual is a comprehensive guide for the classification and identification of prokaryotic bacteria, established by David Hendricks Bergey in 1923. It categorizes bacteria based on various criteria such as morphology, gram staining, oxygen requirements, and genetic relationships, and consists of multiple volumes focusing on different bacterial groups. The manual serves important roles in research, clinical diagnostics, and industrial applications, continuously updated to integrate phenotypic and molecular data.

1. BERGEY’S MANUAL
CLASSIFICATION
MOHD ARSHAN
MSC IN MICROBIOLOGY

2. INTRODUCTION
 .A DUAL-PURPOSE MANUAL:
 SYSTEMATIC BACTERIOLOGY:
FOR TAXONOMY AND
PHYLOGENY.
 DETERMINATIVE
BACTERIOLOGY: FOR
IDENTIFICATION IN
LABORATORIES.
Bergey’s manual classification is a manual
referring to the taxonomy of prokaryotic
bacteria .It was prepared by the American
bacteriologist , “DAVID HENDRICKS BERGEY”
in 1923 . It is a manual that deals with the
identification of bacteria

3. CLASSIFICATION CRITERIA
Key Characteristics for Classification:
 Morphology: Shape, size, and arrangement of cells (e.g., cocci, bacilli).
 Gram Staining: Gram-positive vs. Gram-negative bacteria.
 Oxygen Requirements: Aerobes, anaerobes, facultative anaerobes.
 Biochemical Properties: Enzyme production, fermentation patterns, etc.
 Genetic Relationships: 16S rRNA sequencing and other molecular markers.

4. PRODUCT OVERVIEW

6. (gram positive bacteria)
(Large group of gram negative bacteria )

7. VOLUME 1: THE ARCHAEA AND
THE DEEPLY BRANCHING AND
PHOTOTROPHIC BACTERIA
• Key Features :
• Focuses on evolutionarily ancient bacteria and archaea.
• Includes extremophiles and phototrophic bacteria.
• Major Groups:
• 1. Archaea
• Thermophiles ( Thermoplasma ), halophiles (Halobacterium),
• methanogens ( Methanococcus )
• 2. Deeply Branching Bacteria
• Hyperthermophilic bacteria like Aquifex and Thermotoga .
• 3. Phototrophic Bacteria
• Green sulfur bacteria (Chlorobium) .
• Green non-sulfur bacteria (Chloroflexus).
• Ecological Roles : Thrive in extreme environments .
• Early ancestors of modern prokaryotes.

8. VOLUME 2: THE PROTEOBACTERIA
(GRAM-NEGATIVE BACTERIA)
• Key Features:
• Largest and most diverse phylum.
• Comprises five classes of Gram-negative bacteria.
• Subgroups (Classes):
• 1 Alpha- proteobacteria
• Includes nitrogen-fixing bacteria (Rhizobium) , rickettsias
• 2. Beta- proteobacteria
• Examples: Neisseria ( causes gonorrhea ) , Bordetella (causes
pertussis).
• 3. Gamma- proteobacteria
• Includes Escherichia coli, Pseudomonas, Salmonella.
• 4. Delta- proteobacteria
• Sulfate -reducing bacteria, predatory bacteria like Bdellovibrio .
• 5. Epsilon- proteobacteria
• Pathogens like Helicobacter pylori, Campylobacter.
• Ecological Roles:

9. VOLUME 3: THE FIRMICUTES (LOW G+C
GRAM-POSITIVE BACTERIA)
• Key Features :
• Gram-positive bacteria with low G+C content in their DNA
• Includes both spore-forming and non-spore-forming bacteria
• Major Groups:
• 1 .Bacillus and Clostridium (Spore-formers)
• Bacillus anthracis (anthrax), Clostridium botulinum (botulism).
• 2. Lactic Acid Bacteria
• Lactobacillus, Streptococcus.
• 3. Non-Spore Formers
• Staphylococcus (skin infections), Listeria (foodborne
pathogens)
• .Ecological and Industrial Importance :

10. VOLUME 4: THE PLANCTOMYCETES, SPIROCHAETES,
FIBROBACTERES, BACTEROIDETES, AND OTHERS
KEY FEATURES:
Covers diverse phyla that do not fit neatly into previous categories.
MAJOR GROUPS:
SPIROCHAETES
Spiral -shaped bacteria like Treponema pallidum (syphilis) and Borrelia (Lyme disease).
2. BACTEROIDETES
Includes gut microbiota like Bacteroides (important for digestion).
3. PLANCTOMYCETES
Bacteria with unusual cell walls and internal compartments.
4. CHLAMYDIAE
Obligate intracellular pathogens like Chlamydia trachomatis.
5. OTHER PHYLA:
Fusobacteria, Verrucomicrobia, Acidobacteria, and others.
ECOLOGICAL AND MEDICAL IMPORTANCE:
Pathogens, commensals, symbionts.

11. Click icon to add picture
VOLUME 5: THE ACTINOBACTERIA
(HIGH G+C GRAM-POSITIVE
BACTERIA)
• Key Features :
• Gram-positive bacteria with high G+C content in their DNA.
• Known for their complex life cycles and secondary metabolites.
• Major Groups:
• Actinomycetes
• Streptomyces: Antibiotic producers (streptomycin, tetracycline).
• . Mycobacterium
• Mycobacterium tuberculosis (causes TB), Mycobacterium leprae
(causes leprosy).
• Corynebacterium
• Corynebacterium diphtheriae (causes diphtheria).
• Ecological Roles;
Decomposers, antibiotic production, pathogens.

12. Volume Key example
Volume 1 Archaea and
phototropic bacteria
Halobacterium,
chlorobium .
Volume 2 Proteobacteria Escherichia coli ,
helicobacter pylori
Volume 3 Firmicutes Bacillus ,
lactobacillus ,clostridiu
m
Volume 4 Actinobacteria Streptomyces ,mycoba
cterium
Volume 5 Diverse Bacteroides ,treponem
a pallidum
Summary ;

13. ADVANTAGE OF BERGEY’S MANUAL
• Standardized classification for
global use.
• Integrates phenotypic and
molecular data .
• Continuously updated to
reflect scientific
advancements.
Content

14. APPLICATION OF BERGEY’S MANUAL
• 1 .Research Applications:
• Framework for studying microbial
diversity
• .Reference for phylogenetic and
taxonomic studies
• .2. Clinical Diagnostics:
• Identifying bacterial pathogens.
• Guides in antibiotic sensitivity
testing
• .3. Industrial Uses:
• Identifying microbes for
biotechnology (e.g., fermentation,
enzyme production).

15. CONCLUSION
Content:
• Bergey’s Manual is a cornerstone of microbiology.
• Combines classical phenotypic methods with advanced
molecular techniques.
• Essential for understanding, identifying, and utilizing
microbial diversity.

16. THANK YOU
MOHD. ARSHAN