However, the course will focus on the phylogenetic tree and especially the species whose phenotypic characteristics are best known will be discussed. Thousands of bacteria species are known. Bacteria: Proteobacteria

Bacteria: Proteobacteria

 Thousands of bacteria species are known.

 However, the course will focus on the phylogenetic tree and especially the species whose phenotypic characteristics are best known will be discussed.

 First ancestral phylum is Aquifex

 All of these are hyperthermophilic chemolitotrophs that oxidize H₂

 Other large group gram-positive bacteria and cyanobacteria

 Gram positive bacteria are Firmicutes and

Actinobacteria. Thus, it can be divided into two subgroups.

 Proteobacteria is the largest and most metabolically active group in Bacteria.

 It includes medicinal, industrial and agriculturally important bacteria.

 All of are Gram negative bacteria.

 It has a wide range of energy production mechanisms with its chemolitotrophic,

chemoorganotrophic and phototrophic types.

 There are anaerobic, microaerophilic, facultative

aerobic types according to their relationship with O₂.

 They can be straight or curved bacillus, coke, spiral, flamenteous.

 According to 16 S rRNA gene analyzes, the Proteobacteria is divided into 6

classes:

 Alphaproteobacteria

 Betaproteobacteria

 Gammaproteobacteria

 Deltaproteobacteria

 Epsilonproteobacteria

 Zetaproteobacteria (Mariprofundus,

currently known as Fe oxidizing marine bacteria)

Purple Phototrophic Bacteria

 For example; Rhodobacter

 Purple sulfur bacteria

 Purple non-sulfur bacteria

 They are anoxygenic phototrophes.

 Unlike Cyanobacteria, they do not produce O₂.

 They contain bacteriochlorophyll and carotenoid pigments.