Soli 1892 olimi rus D.I.Ivanovskiy dar tamoku bemoriero mushohida kard. Barangezandai on gayriodi buda, dar barghoi tamoku doghoi gunogun paydo megardad. Barangezanda qobiliya- ti az filtr guzashtanro dosht. Binobar in, rustanihoi solimi tamokuro bo shirai az filtr guzashtai rustanihoi bemor siroyat- nok kardan mumkin ast.
Badi chand sol olimon L.Leffler va P.Frosh angezandai be- morii okhsilro paydo kardand, ki on dar hayvonot, az chumla dar chorvo dida shuda, angezandaash az filtr meguzarad.
Okhiri soli 1917 bakteriolog az Kanada F. Erell bakteri- ofagro kashf namud, yane virushoe, ki bakteriyahoro mahv me- sozand. Hamin tariq, virusi rustaniho, hayvonot va mikroor- ganizmho kashf karda shud. Hamai in boisi paydoishi ilmi nav – virusologiya gardid. Virusho dar hayoti inson naqshi khele ka- lonro mebozand. Onho angezandai bisyor bemorihoi khavfnok, masalan, diqqi nafas, zardparvin, ensefalit, surkhakon, surkhcha, de- vonagi, zukom va gayra meboshand. Virusho faqat dar hujayraho faoliyat mekunand, binobar in, onhoro paraziti dokhilihujay- ravi menomand.
Onho ozod va berun az muhiti hujayra faoliyat va afzoish karda nametavonand. Agar dar hamai organizmhoi hujayrador hamon du shakli kislotai nukleinii KDN va KRN dida shavad, dar virusho faqat yake az onho vomekhurad.
Virusi kasalii dogi bargi tamoku:
- – gilofai safedagi,
- – KRN.
Binobar in, virusho ba du guruhi kalon judo karda mesha- vand, yane virushoi dorandai KDN va virushoi dorandai KRN. Virusho ba hujayra faqat akhbori genetikii khudro meguzaronand. Az qolabi KRN yo KDN virusi KRN akhbori khudro sintez meku- nand, ki in zamina baroi sintezi safedahoi ribosomahoi hujay- rahoi bo virus giriftorbuda khos ast.
Molekulai KDN yo genomi on dar genomi sohibi hujayra joy- gir ast va dar holati oromi muddati duru daroz meistad.
Hamin tariq, khususiyati muftkhuri virus khosiyati khosro doshta, hamchun parazit dar darajai genetiki ba hisob meravad.
Tarkibi khimiyavii virusho
Virusho az nukleoproteidho, yane az kislotahoi nukleinat (KDN va KRN), inchunin, az chand safeda, ki pardai atrofi kis- lotahoi nukleinatro ihota kardaand, tashakkul yoftaand. Pardai safedagiro gilofa (kapsula; az kalimai lotinii sarzo – gunjo- ish) menomand. Ba chunin virusho virusi doghoi tamoku misol me- boshad. , ki gilofa – qabati safedai on az yak safedai nachandon kalon iborat ast.
Virushoi tashakkulashon murakkab pardai ilovagi dorand, ki az safeda yo lipoprotein sokhta shudaast. Bazan dar pardai berunii virushoi murakkab angishtobho dida meshavand, masa- lan, dar virusi angezandai zukom va tabkhol . Pardai berunii onhoro qismhoi membranai yadro va sitoplazmai hujay- rahoi sohib (homil) tashkil karda, virus az on ba muhiti berun mebaroyad. Genomi virusho az yak molekulai yaktora yo dutorai KDN va KRN iborat ast. Ba KDN-i dutora virusi bemorii nagzaki odam, gusfand, khuk, adinovirushoi odam dokhil meshavand. KRN-i dutora hamchun qolabi genetiki baroi baze virushoi hasharot va hayvonot khizmat mekunad. Hamchunin, virushoi KRN-i yakto- ra vase pahn gashtaand, ba monandi virusi ensefalit, surkhakon, surkhcha, devonagi, zukom va gayra.
Tasiri tarafayni virus ba hujayra
Hangomi ba vujud omadani vakuolahoi pinositozi hamrohi qatrahoi moei muhiti baynihujayravi ba daruni hujayra taso- dufan virusho dokhil meshavand. Onho dar muhiti moe gardish mekunand. Vorid shudani virusho ba sitoplazmai hujayra bo chand zinahoi payiham aloqamand ba amal meoyad. Saravval, vi- rus bo safedai retseptorii makhsus, ki dar boloi pardai hujayra joygir ast, payvast meshavad. In amal bo yorii safedahoi makh- sus, ki dar boloi zarrachahoi virusi mavjudand, ba amal meoyad. Safedaho retseptorhoi ba khud muvofiqro, ki dar boloi hujayra joygirand, meshinosand. On qismi boloi hujayra, ki bo virus payvast shudaast, dar sitoplazma furu rafta, ba vakuola tabdil meyobad. Vakuola, ki devorai on az membranai sitoplazmavi sokhta shudaast, metavonad bo digar vakuolaho yo bo yadro yakjoya shavad (rasmi 5.25). Bo hamin roh, virus ba tamomi hujayraho burda me- shavad. Mekhanizmi retseptorii voridshavii virus ba hujayra bo khususiyati makhsusi ravandi siroyatyobi vobasta ast.
Az in jost, ki virusi hepatiti A va V tanho ba hujayrahoi jigar dokhil shuda, afzoish meyoband. Adinovirus va virusi zukom dar hujayrahoi luobpardai rohi nafas, virusi sarkom dar hujay- rahoi asab, virusi khanozir (bungushi) faqat dar hujayrahoi naz- di gush va gadudi obi dahon vomekhurand.
Dar vaqti duchandshavi (reduplikatsiya) kislotai nukleinat az pardai kapsidi judo megardad. Badi sintezi molekulai navi kislotai nukleinat bo safedai virusi dar sitoplazmai hujay- rai homil sintezshuda ihota meshavad va kapsidro tashkil me- kunad. Dar natija, virusho afzuda, az hujayra berun meshavand. In holat dar baze virusho dar shakli tarkish ba amal omada, hujayraho mahv meshavand. Horij shudani virushoi digar misli mugjabandist va hujayrahoi in organizmho muddati madid qobi- liyati hayotii khudro nigoh medorand. Rohi digari ba hujayra do- khil shudani virushoi bakteriyaho, yane bakterofagi meboshand. Qabati gafsi bakteriya imkon namedihad, ki safedai retseptor ba virus payvast shuda, ba sitoplazma roh yobad, misli on ki dar hujayrahoi siroyatnoki hayvonot ba amal meoyad. Baroi hamin bakteriofag dumchai khudro ba devorai hujayrai bakteriya kha- londa, KDN yo KRN-i dar sarak doshtai khudro ba sitoplazmai bakteriya vorid mekunad (rasmi 5.26). Hamin tavr, genomi bak- teriofag furu rafta, kapsidi on dar berun memonad. Genom dar sitoplazmai hujayrai bakteriya duchand shuda, ba sintezi safeda va kapsid asos meguzorad.
Badi chand muddat hujayrai bakteriya mahv gashta, zarra- chahoi faghoi pukhtarasida ba berun mebaroyand va metavonand bakteriyai digarro nobud kunand.
Paydoishi virusho
Virusho hamchun sokhtori genetiki mukhtor buda, berun az hujayra qobiliyati inkishof yoftan nadorand, yane jismi bejo- nand. CHunin meshumorand, ki virusho va bakteriofagho hamchun unsuri genetikii judogonai hujayra buda, hamrohi digar shaklhoi hayoti hujayravi inkishof yoftaand.
Savolho baroi sanjish:
- Sokhti virusho chi guna ast?
- Virushoi soda az murakkab bo chi farq mekunand?
- Prinsipi tasiri mutaqobilai virus va hujayra chi guna ast?
- Virus chi tavr ba hujayra dokhil meshavad?
- Tasiri mutaqobilai bakteriofaghoro ba hujayrai bakteriya sharh dihed.
- Tasiri virusho ba hujayra chi guna ast?
Istilohot:
- Virus – shakli gayrihujayravii hayot.
- Bakteriofag – virushoe, ki bakteriyaho yo fagahoi onhoro mahv me- sozand.
- Siroyat – rohi intiqoli angezaho az yak organizm ba organizmi digar.
- Bo rohi ufuqi guzashtan – rohi guzashtani omili siroyatkuni bo hujayrahoi jinsi, ki dar khromosomai on mavoddi irsi – virus joygir meshavad.
- Bo rohi amudi guzashtan – ravandi bohamtasirkunii virus va or- ganizmi sohib, ki hamchun muftkhur dokhil shuda, afzoish yofta, ba muhiti beruna mebaroyad.
- Nazariyai hujayragi – yake az khulosahoi muhimtarini biologi, ki muvofiqi on hamai organizmho sokhti hujayragi dorand.
Testho
- Avvalin bor virusro kadom olim mushohida namud?
a) D.Ivanovskiy; b) Leffer; v) P.Frot.
- Bakteriofagro ki kashf kard?
a) R.Vikhrov; b) F.Erell; v) I.Ivanovskiy.
- Kadom virushoro bakteriofaga menomand?
a) virushoi odam; b) virushoi hayvonot; v) virushoe, ki bakteriyaho- ro nest mekunand.
- Virusho dar kadom holat faoland?
a) berun az huchayra; b) tanho dar daruni hujayra; v) dar muhiti girdu atrof.
- Dar virusho kadom shakli kislotahoi ribonukleinat mavchudand?
a) tanho KDN yo tanho KRN; b) ham KDN va ham KRN; v) yagontai az inho.
- KRN-i dutora baroi kadom bemoriho khos ast?
a) bemorii nagzaki odam; b) zukom; v) surkhakon.
- Kadom virusho KRN-i yaktora dorand?
a) surkhcha; b) odenovirusi odam; v) odenovirusi gusfand.
- Virusho dar kucho afzoish mekunand?
a) dar huchayrahoi sohib; b) dar muhiti beruna; v) khud az khud.
- Virusi gepatiti A kadom huchayraro siroyat mekunad?
a) huchayrai asab; b) huchayrai chigar; v) huchayrai rohi nafas.
- Kalimai «virus» az kadom zabon kirifta shudaast va chi mano dorad?
a) az zaboni anglisi – zahr; b) az zaboni lotini – zahr; v) az zaboni rusi – zahr.