Exercise 2

Rhizobium nitrogen-fixing

• rod

• circles are bacteroid

• light brown to orange

• gram negative

• for nitrogen fixation

Spirillum

• spiral

• in singles

• pink

• gram negative

Enterobacter aerogenes

• rod (bacilli)

• typically in singles, sometimes in pairs or short chain

• pink or red

• gram negative

• important in nutrient cycling

Mycobacterium tuberculosis

• rod

• violet/purple

• gram positive

• in singles or in pairs , small clumps

Proteus vulgaris

• rod

• in singles, or in clusters

• pink or red

• gram negative

• urinary tract infections (UTIs), cause wound infections, respiratory tract infections

Streptococcus sp.

• Spherical (cocci)

• Chains or pairs

• Purple or blue

• Gram-positive

• Strep throat/pneumonia, spread through respiratory droplets or direct contact

Staphylococcus aureus.

• Spherical (cocci)

• Clusters, resembling grape-like formations

• Purple or blue

• Gram-positive

• Skin and soft tissue infections (boils/abscesses), spread through direct contact

Diplococcus pneumoniae

• Spherical (cocci)

• Pairs (diplococci)

• Purple or blue

• Gram-positive

• Pneumonia, meningitis, spread typically through respiratory droplets

Sarcina lutea

• Spherical (cocci)

• Cubical packets of 8 cells (sarcina arrangement)

• Purple or blue

• Gram-positive

• Non-pathogenic and rarely causes diseases

Pseudomonas aeruginosa

• Rod-shaped (bacilli)

• typically in singles, sometimes in pairs or short chain

• Pink or red (Gram-negative)

• metabolic versatility, adaptability to changing environments, and ability to survive in challenging habitats.

Corynebacterium glutamicum

• Rod-shaped (bacilli), slightly club-shaped (pleomorphic)

• Palisades (aligned in parallel) or in V-shaped groupings

• Purple or blue (Gram-positive)

• a major workhorse in industrial biotechnology

Shigella dysenteriae

• Single cells (could also be in short chains)

• Pink

• Gram negative

• contaminates water, causes Shigellosis

Salmonella typhosa

• Rod (bacillus)

• Single cells (could also be in short chains)

• Pink

• Gram negative

• causative agent of Typhoid Fever

Treponema pallidum

Helical (spiral-shaped), tightly coiled which is typical of spirochetes

Single cells

Pink (Gram negative)

• pathogen (does not survive well outside the human body), causative agent of Syphilis

Bacillus subtilis

• Rod-shaped (bacilli)

• Single or in chains

• 4.0 to 10.0 micrometers

• Purple or blue (Gram-positive)

• Non-pathogenic bacteria found in the soil or the human gut. It is usually used for probiotic and food production.

Escherichia coli

• Rod-shaped (bacilli)

• Single or in pairs

• 1.0 to 3.0 micrometers

• Pink or red (Gram-negative)

• Found in the intestines of humans and animals, where most strains are harmless. But some can cause gastrointestinal infection (food poisoning), UTI, Sepsis, Pneumonia, and Neonatal Meningitis.

Spirillum

• Spiral-shaped (spirilla)

• Single

• 1.4 to 1.7 micrometers in diameter and 6 to 15 micrometers in length

• Typically pink or red (Gram-negative)

• most commonly found in stagnant water, rich in organic material. While many species are non-pathogenic, some can cause infections in humans. Such as ___ minus can cause Rat-Bitten-Fever.

Klebsiella pneumoniae

• Shape: Rod-shaped (bacilli)

• Arrangement: Single or in pairs

• Size: 1.0 to 2.0 micrometers

• Gram Stain Color: Pink or red (Gram-negative)

• A normal flora of the intestines, but can cause serious infections. Such as Pneumonia, UTI, Sepsis, Wound infections, Meningitis, and Liver Abscess.

Serratia marcescens

• Rod-shaped (bacilli)

• typically singles or in pair or short chains

• 1.0 to 2.0 micrometers

• pink or red (Gram-negative)

• opportunistic human pathogen in hospitals and as a plant growth promoting bacteria (PGPR) in crops

Clostridium perfringens

• Rod-shaped (bacilli)

• Arrangement: Single or in short chains

• Size: 3.0 to 8.0 micrometers

• Gram Stain Color: Purple or blue (Gram-positive)

• providing agroecological benefits in plant-growth promotion

Alcaligenes faecalis

• Rod (bacillus)

• singles or in pairs

• Pink

• Gram negative

• trigger local infections, including peritonitis, meningitis, otitis media, appendicitis, and bloodstream infection

Lactpbacillus sp.

• Rod-shaped (bacilli)

• Single or in chains

• 4.0 to 10.0 micrometers

• Purple or blue (Gram-positive)

• Non-pathogenic bacteria found

• safe for use in food (probiotics and to ferment food)