Effect of ionizing radiation on haemoglobin of marine lamellibranchs

✍ Scribed by S. Patel; B. Patel

• Publisher: Springer-Verlag
• Year: 1971
• Tongue: English
• Weight: 728 KB
• Volume: 10
• Category: Article
• ISSN: 0025-3162
• DOI: 10.1007/bf00352818

✦ Synopsis

The effect of ionizing radiation on the iron-linked protein (haemoglobin) of the marine lamellibranchs Anadara granosa (LI~N.) and Cardita antiquata (LA~[.) from Bombay waters, India is discussed. Purified haemoglobin solutions were exposed to a 6~ source delivering a dose o{ about 4,600 rad/ min, at the sample irradiation point. Radiation damage or degradation was measured spectrophotometrically by studying changes in the absorption spectra following irradiation in the presence and absence of oxygen. Exposure to ionizing radiation in general caused a decrease in absorption of both haemoglobins, irrespective of location, viz extra-versus intracellular, at Soret (412 miz), fl (540 to 42 m~) and cr (574 to 76 miz) peaks, and an increase in absorption at 510 and 630 m~. Upon exposure to a higher dose, 02Hb of C. antiquata showed an increase in absorption at the protein peak (280 m~) ; exposure to a lower dose, however, resulted in decreased absorption. Furthermore, the changes following irradiation were dependent upon the initial state of the pigment. Oxyhaemoglobin, when exposed to radiation, oxidized to hemiglobin, and hemiglobin reduced to oxyhaemoglobin. The extracellular haemoglobin of high molecular weight (3 • i06) of the false cockle C. antiquata was found to be extremely radio-resistant, whereas intracellular haemoglobin of low molecular weight (74,000) of the arcid clam A. granosa was highly radiosensitive, since it could not be exposed to doses exceeding 18,000 r.