Yes, B.Sc in Microbiology candidates can get jobs in ISRO.
The eligibility criteria for ISRO is given below-
You should be a student of science or engineering stream from a recognized college or university with above 60% marks from the following branches only :
Electrical and Electronics, Biotechnology, Agricultural Science, Civil Engineering, Chemistry, Computer Science, Geology, Psychology, Physics, Computer Science, Pharmacy, Nursing, Botany, Automobile Engineering, Metallurgy, Veterinary Science Zoology, Library Science, Photography, Electrical, Physics, Radiography, Die and Molding, Tool, Mechanical, Textile, Instrumentation, Chemical Engineering, Printing
Final year students can also apply for ISRO exam.
Your age should be in between 21 to 30 years.