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BAKTERIYAHO

bacteriaBAKTERIYAHO (Bacteria; az yun. bakterion – chubcha), mikroorganizmhoi asosan yakhujayra, ki dar tabiat nihoyat farovonand.
B.-ro bori avval dar a. 17 olimi gollandi A. Levenguk oshkor kard. Omuzishi daqiqi khususiyathoi biologii B. bo nomi olimi fransavi L. Paster, mikrobiologi nemis R. Kokh va olimi anglis D. Lister marbut ast. B. chubshakl, kurashakl (kokkho), spiralshakl (spirokhetaho), vergulshakl (vibrionho) va g. meshavand. Darozii B.-i chubshakl 1 – 8 mkm, barashon 0,5 – 2 mkm, diametri B.-i kurashakl 0,5 – 1 mkm ast (1 mkm – az hazor yak hissai millimetr). B. bo devorai hujayravi va gisho (membrana)-i sitoplazmavi faro girifta shuda, sitoplazmai qabat-qabat, dona-dona va naychashakl dorand. Hujayrai B. az kislotai dezoksiribonukleat va ribosoma, ki dar tarkibash kislotai ribonukleat dorad, iborat ast. B. hamchun organizmhoi saprofit (gizoyashon boqimondai moddahoi gunoguni organikist) yo parazit gizo megirand. Baze navhoi B. (mas., B.-i azotanduz) az moddahoi noorganiki moddahoi organiki hosil mekunand. Vobasta ba tarzi nafasgiri B. ba aerobho, mikroaerofilho (dar mavridi past shudani fishori juzii oksigen inkishof meyoband) va anaerobho (baroi inkishofi onho oksigen lozim nest) judo meshavand. Dar ravandi faoliyat B. ba muhit fermenti ziyod ikhroj menamoyand. Baze B. qabati berunii muhofiz (kapsula, spora va g.) dorand. Dar B. tagyirpaziri, mutobiqat va ustuvori bar ziddi tasiri zararnok nazar ba dig. organizmho beshtar ast. Ba bisyor B. ziddiyati baynihami, muqobilat bo mikroorganizmhoi digar, inchunin holati simbioz (hamzisti) khos meboshad. Aktinomisetho, mikoplazmaho va g. guruhhoi asosii B.-ro tashkil medihand.
Vobasta ba tarkibi khimiyavi B. az hujayrai organizmhoi digar tafovut nadorand. Hujayrai B. az 75 – 85% ob iborat ast. Taqr. 90%-i boqimondai khushkro payvasthoi molekulaashon kalon – kislotahoi nukleinat (10%), safedaho (40%), polisakharidho (15%), peptidoglikan (10%) va lipidho (15%) tashkil medihand.
Dar rafti hayoti B., misli organizmhoi digar, fermenthoi sershumor shirkat mevarzand. Bazei onho (mas., endofermentho) faqat dar dokhili hujayra faoliyat karda, ravandi sintez, nafaskashi va g.-ro tamin mesozand. Fermenthoi digar (ekzofermentho)-ro B. ba muhit ikhroj menamoyand.
Bahri rushdu afzoishi B. boyad muhiti sukunat ba miqdori kofi gazi karbonat, nitrogen, namakhoi gunogun va harorati muvofiq doshta boshad. Baroi bisyor B.-i bemorizo harorati sozgor 370 ast (yane muvofiq ba harorati badani odamu hayvonot).
Ba faoliyati B. harorat, nami, afkanishoti ultrabunafsh va ionnok tasir merasonand. B. ba sarmo tob meorand. Bazei onho dar sarmoi 190S (sporaho dar – 2530S) niz metavonand faoliyat doshta boshand. Vale az garmii ziyod onho zud nobud meshavand; B.-i bespora dar haror. 60 – 700 va sporador dar haror. ziyoda az 1000 mahv megardand.
Darajai bardoshti B. ba beobi niz gunogun ast. Mas., gonokokkho binobar khushkidan zud mefavtand; faoliyati B.-i isholi khunin to 7 ruz, guluzindonak – 30 ruz, domana – 70 ruz, bemorii sil – 90 ruz, sporahoi batsillai sukhtani to 10 sol mahfuz memonad. B. ba afkanishoti ultrabunafsh, az jumla ba nuri bevositai oftob, hassos meboshand.
Az miqdori beintihoi B.-e, ki dar tabiat mavjudand, faqat adadi kami onho boisi paydoishi bemoriho meshavand. B.-i bemoriovar badi ba organizm aftodan, zahr – ekzotoksin hosil mekunand (mas., angezahoi khunoq, botulizm, kuzoz va g.). Ekzotoksinho nihoyat zahrnok meboshand: 5 kg zahri botulizm yo 7 kg enterotoksini stafilokokkho metavonad ziyoda az 5 mln l obro siroyatnok sozad.
Baze B. (salmonellaho, mikrobhoi ruda, angezandahoi isholi khunin, gonokokkho va g.) endotoksin hosil mekunand. Zahrnokii endotoksinho nisbatan sust buda, onho ba boftaho tasiri intikhobi nadorand; endotoksin zeri tasiri formaldegid ba anatoksin tabdil nameyobad.
B. dar khok, ob havo, organizmi odam va hayvonot mavjud buda, dar mubodilai moddaho dar tabiat, barqaror sokhtani zakhirai gazi karbonat (CO2) dar atmosfera va gizohoi mineralii nitrogendor dar khok (baroi sabzishi rastaniho zarurand) ahamiyati kalon dorand. Baze B. baroi hosil kardani antibiotikho, fermentho, spirt, vitaminho, kislotahoi organiki va g., inchunin dar tahvili pakhta, abreshim, qahva, kauchuk, silosonii khuroki chorvo va g. ahamiyati kalon dorand. B.-i digar boisi pusish va turshii ozuqavori va dig. anvoi mahsulot megardand. B. angezandai bisyor bemorihoi odam (vabo, isholi khunin, domana, toun, khunoq, sil, brutsellyoz va g.), hayvonot (mas., sukhtani va g.) va rastani (tosaki kartoshka va g.) meboshand. Baze B.-i bemoriovar va zahri onho baroi tayyor kardani vaksina va zardobi tabobati ba kor meravand. Bar ziddi B.-i zararnok az vositahoi fiziki (harorati baland, nuri ultrabunafsh va g.) va khimiyavi (moddahoe, ki bakteriyahoro mahv mekunand yo inkishofi onhoro sust megardonand) istifoda mebarand.

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