Paenibacillus
alginolyticus - alvei - amylolyticus - apiarius - azoreducens - azotofixans - chibensis - chondroitinus - curdlanolyticus - glucanolyticus - jamilae - larvae - lautus - lentimorbus - macerans - macquariensis - pabuli - peoriae - polymyxa - thiaminolyticus - validus

Pantoea
agglomerans - dispersa

Paracoccus
alcaliphilus - alkenifer - denitrificans - kocurii - kondratievae - pantotrophus - sp. - thiocyanatus

Paracraurococcus
ruber

Paralactobacillus
selangorensis

Pasteurella
skyensis - sp.

Paucimonas
lemoignei

Pectinatus
cerevisiiphilus

Pediococcus
acidilactici - damnosus - dextrinicus - inopinatus - parvulus - pentosaceus - sp.

Pedobacter
africanus - heparinus - piscium - saltans

Peptoniphilus
asaccharolyticus - indolicus

Persicobacter
diffluens

Phaeospirillum
fulvum - molischianum

Phenylobacterium
immobile

Photobacterium
angustum - damsela - iliopiscarium - leiognathi - mandapamensis - phosphoreum - sp.

Photorhabdus
luminescens

Phyllobacterium
myrsinacearum - rubiacearum

Pigmentiphaga
kullae

Pilimelia
anulata - columellifera - terevasa

Planctomyces
brasiliensis - maris

Planobispora
longispora

Planococcus
alkanoclasticus - citreus - kocurii - sp.

Planomicrobium
okeanokoites

Planotetraspora
mira

Plesiomonas
shigelloides

Polyangium
cellulosum

Pragia
fontium

Prauserella
rugosa

Promicromonospora
citrea

Propionibacterium
acidipropionici - avidum - cyclohexanicum - freudenreichii - granulosum - intermedium - jensenii - lymphophilum - sp. - thoenii

Prosthecobacter
fusiformis

Prosthecomicrobium
enhydrum - litoralum - pneumaticum

Protaminobacter
thiaminophaga

Proteus
hauseri - mirabilis - myxofaciens - penneri - sp. - vulgaris

Providencia
rettgeri

Pseudoalteromonas
atlantica - bacteriolytica - carrageenovora - citrea - denitrificans - elyakovii - espejiana - flavipulchra - haloplanktis - luteoviolacea - nigrifaciens - piscicida - rubra - sp. - tetraodonis - ulvae - undinda

Pseudoaminobacter
defluvii

Pseudomonas
aeruginosa - aestumarina - alcaligenes - anguilliseptica - antimicrobica - antimycetica - aromatica - aurantiaca - beijerinckii - boreopolis - chlororaphis - citronellolis - cohaerens - cruciviae - dehalogenans - denitrificans - deva - diazotrophicus - effusa - elodea - elongata - ephemerocyanea - fluorescens - fragi - frederiksbergensis - graminis - huttiensis - iners - insueta - kilonensis - lanceolata - lindbergii - lundensis - mendocina - mephitica - migulae - mucidolens - myxogenes - nitroreducens - oceanica - oleovorans - pictorum - plecoglossicida - pleomorpha - proteofaciens - pseudoalcaligenes - putida - rathonis - resinovorans - rhodesiae - saccharophila - salopia - septica - sp. - stanieri - stereotropis - stutzeri - syncyanea - synxantha - syringae - taetrolens

Pseudonocardia
autotrophica - halophobica - hydrocarbonoxydans - petroleophila - saturnea - sulfidoxidans - thermophila

Psychrobacter
frigidicola - immobilis - sp. - urativorans

Psychroflexus
gondwanensis

Psychromonas
marina