| Origin | Code | Comment | Supplementary Taxo |
| Paenibacillus naphthalenovorans | ISPana | | |
| Paenibacillus polymyxa | ISPap | | |
| Paenibacillus sp. | ISPaen | | |
| Pandoraea faecigallinarum | ISPfa | | |
| Pandoraea pnomenusa | ISPpn | | |
| Pandoraea thiooxydans | ISPath | | |
| Pantoea agglomerans | ISPag | | |
| Pantoea ananatis | ISPan | | |
| Pantoea sp. | ISPansp | | |
| Parabacteroides sp. | ISPrsp | | |
| Paraburkholderia caffeinilytica | ISPaca | | |
| Paraburkholderia hospita | ISPho | | |
| Paraburkholderia sp. | ISParsp | | |
| Paracaedibacter acanthamoebae | ISParac | | |
| Parachlamydia acanthamoebae | ISPaac | | |
| Parachlamydia sp. | ISPasp | | |
| Paracoccus aestuarii | ISPaes | | |
| Paracoccus alcaliphilus | ISPlc | | |
| Paracoccus alkenifer | ISPak | | |
| Paracoccus aminophilus | ISPam | | |
| Paracoccus bengalensis | ISPbe | | |
| Paracoccus denitrificans | ISPde | | |
| Paracoccus ferrooxidans | ISPfe | | |
| Paracoccus haeundaensis | ISPhae | | |
| Paracoccus halophilus | ISPha | | |
| Paracoccus kondratievae | ISPko | | |
| Paracoccus koreensis | ISPkr | | |
| Paracoccus marcusii | ISPmar | | |
| Paracoccus methylutens | ISPme | | |
| Paracoccus pantotrophus | ISPpa | | |
| Paracoccus seriniphilus | ISPse | | |
| Paracoccus solventivorans | ISPso | | |
| Paracoccus thiocyanatus | ISPth | | |
| Paracoccus versutus | ISPve | | |
| Paracoccus yeei | ISPye | | |
| Paracoccus yeeii | ISPye | | |
| Paracoccus zeaxanthinifaciens | ISPze | | |
| Paraliobacillus quinghaiensis | ISPqu | | |
| Parvarchaeum acidophilus | ISPac | | |
| Parvibaculum lavamentivorans | ISPla | | |
| Pasteurella multocida | ISPmu | | |
| Pectobacterium atrosepticum | ISPeat | | |
| Pectobacterium carotovorum | ISPcc | | |
| Pediococcus inopinatus | ISPein | | |
| Pediococcus pentosaceus | ISPpe | | |
| Pelagibaca bermudensis | ISPebe | | |
| Pelagibaca sp. | ISPep | | |
| Pelobacter carbinolicus | ISPca | | |
| Pelobacter propionicus | ISPepr | | |
| Pelodictyon luteolum | ISPelu | | |
| Pelodictyon phaeoclathratiforme | ISPph | | |
| Pelomonas sp. | ISPels | | |
| Pelotomaculum sp. | ISPelsp | | |
| Pelotomaculum thermopropionicum | ISPeth | | |
| Petrimonas mucosa | ISPemu | | |
| Photobacterium damselae | ISPda | | |
| Photobacterium kishitanii | ISPki | | |
| Photobacterium mandapamensis | ISPma | | |
| Photobacterium phosphoreum | ISPhph | | |
| Photobacterium profundum | ISPpr | | |
| Photobacterium sp. | ISPhsp | | |
| Photorhabdus luminescens | ISPlu | | |
| Photorhabdus temperata | ISPte | | |
| Pirellula staleyi | ISPist | | |
| Piscirickettsia salmonis | ISPsa | | |
| Planctomyces maris | ISPlma | | |
| Planctomyces sp. | ISPlas | | |
| Planctomycetes bacterium | ISPlba | | |
| Planktothrix agardhii | ISPlag | | |
| Planktothrix rubescens | ISPlr | | |
| Planococcus antarcticus | ISPlan | | |
| Planococcus donghaensis | ISPdo | | |
| Plesiocystis pacifica | ISPlpa | | |
| Plesiomonas shigelloides | ISPsh | | |
| Pleurocapsa sp. | ISPle | | |
| Pluralibacter gergoviae | ISPlge | | |
| Polaromonas naphthalenivorans | ISPna | | |
| Polaromonas sp. | ISPosp | | |
| Polynucleobacter sp. | ISPlsp | | |
| Pontibacillus chungwhensis | ISPch | | |
| Porphyromonadaceae bacterium | ISPba | | |
| Porphyromonas gingivalis | ISPg | Predefined common nomenclature | |
| Prevotella buccae | ISPbu | | |
| Prevotella multisaccharivorax | ISPrmu | | |
| Prevotella sp. | ISPvsp | | |
| Prevotella tannerae | ISPta | | |
| Prevotella timonensis | ISPti | | |
| Primary endosymbiont of Sitophilus oryzae | ISSoEn | | |
| Prochlorococcus marinus | ISPrma | | |
| Propionibacterium freudenreichii | ISPfr | | |
| Propionibacterium sp. | ISPros | | |
| Prosthecochloris aestuarii | ISPae | | |
| Proteobacteria bacterium | ISPrba | | |
| Proteus mirabilis | ISPmi | | |
| Proteus sp. | ISProsp | | |
| Proteus vulgaris | ISPvu | | |
| Providencia hangzhouensis | ISPrha | | |
| Providencia rettgeri | ISPrre | | |
| Providencia sp. | ISPrs | | |
| Providencia stuartii | ISPrst | | |
| Pseudoalteromonas atlantica | ISPat | | |
| Pseudoalteromonas sp | ISPesp | | |
| Pseudoalteromonas sp. | ISPsesp | | |
| Pseudoalteromonas tunicata | ISPtu | | |
| Pseudomonas aeruginosa | ISPa | Predefined common nomenclature | |
| Pseudomonas alcaligenes | ISPal | | |
| Pseudomonas asiatica | ISPsas | | |
| Pseudomonas atlantica | ISPsal | | |
| Pseudomonas borbori | ISPbo | | |
| Pseudomonas cepacia | ISBuce | | Burkholderia cepacia |
| Pseudomonas entomophila | ISPen | | |
| Pseudomonas fluorescens | ISPfl | | |
| Pseudomonas fulva | ISPsfu | | |
| Pseudomonas geniculata | ISPge | | |
| Pseudomonas huttiensis | ISPhu | | |
| Pseudomonas juntendi | ISPju | | |
| Pseudomonas koreensis | ISPsko | | |
| Pseudomonas kurunegalensis | ISPku | | |
| Pseudomonas mandelii | ISPman | | |
| Pseudomonas mendocina | ISPsme | | |
| Pseudomonas monteilii | ISPmo | | |
| Pseudomonas moorei | ISPsmo | | |
| Pseudomonas oleovorans | ISPol | | |
| Pseudomonas oryzihabitans | ISPor | | |
| Pseudomonas plecoglossicida | ISPpl | | |
| Pseudomonas pseudoalcaligenes | ISPps | | |
| Pseudomonas putida | ISPpu | | |
| Pseudomonas resinovorans | ISPre | | |
| Pseudomonas salegens | ISPssa | | |
| Pseudomonas savastanoi | ISPsav | | |
| Pseudomonas solanacearum | ISRso | | Ralstonia solanacearum |
| Pseudomonas sp. | ISPsp | | |
| Pseudomonas stutzeri | ISPst | | |
| Pseudomonas syringae | ISPsy | | |
| Pseudomonas syringae pv. actinidiae | ISPsy | | |
| Pseudomonas syringe | ISPsy | | |
| Pseudomonas syringe pv. actinidiae | ISPsy | | |
| Pseudomonas taeanensis | ISPsta | | |
| Pseudomonas xanthomarina | ISPxa | | |
| Pseudooceanicola sp. | ISPoc | | |
| Pseudoxanthomonas sp. | ISPxasp | | |
| Pseudoxanthomonas spadix | ISPxsp | | |
| Psychrobacter arcticus | ISPar | | |
| Psychrobacter maritimus | ISPsma | | |
| Psychrobacter piscatorii | ISPpi | | |
| Psychrobacter psychrophilus | ISPpy | | |
| Psychrobacter sp | ISPssp | | |
| Psychroflexus gondwanensis | ISPgo | | |
| Psychroflexus torquis | ISPto | | |
| Psychromonas ingrahamii | ISPin | | |
| Psychromonas sp. | ISPysp | | |
| Pusillimonas sp. | ISPusp | | |
| Pyrococcus furiosus | ISPfu | | |