MTGase Mediated Polymerization of 11S Globulin to Enhance Its Functionalities and the Proteomics

In this paper, the effects of the induced polymerization and modification by microbial transglutaminase (MTGase) on solubility and emulsifiability of soybean 11S globulin was studied. The mechanism was also investigated through proteomics. Using SDS-PAGE and optical density scanning to testify MTGase enzymatic polymerization, the optimum conditions showed that: temperature was 45 °C, ionic condition I was 0.2, pH was 8.0, the amount of enzyme was 30 U/g. The molecular weight of modified 11S globulin subunits concentrated at 15 kDa. The solublity and emulsifiability were significantly enhanced. There were 268 differential protein spots extracted. Ten protein spots had significant differences in expression which totally focused on seed storage proteins, promoting seed germination and maturation proteins, proteins involved in osmotic regulation and alcohol dehydrogenase, which affect solubility and emulsifiability of 11S globulin.

The promotion and suppression of DNA charge neutralization by the cosolute ectoine

Ectoine can promote DNA charge neutralization at mild cosolute concentration in solution. When the concentration of ectoine is high enough, however, a mixing effect of promotion and suppression can be found in the same ionic condition.

Differential role of spermine and thermospermine in Arabidopsis thaliana in response to abiotic stresses

Polyamines (PA) are small organic polycations found in all living organisms. Putrescine (Put), spermidine (Spd), spermine (Spm) and thermospermine (T-Spm) are the most abundant PAs in plants. Of the polyamines (PAs) plant contains at least two types of tetraamines; spermine (Spm) and thermospermine (T-Spm) and they seem to have different functions in plants. The experiment was conducted to eludicate the stress responsive roles of Spm and T-Spm using wild ecotype (Col-0) and three different knockout mutants (spms, acl5 and spms/acl5) of Arabidopsis, differing in the amount of spermine and thermospermine content. First exogenous pretreatment of both tetraamines showed their different effects on plant phenotype including root and shoot length, cholorophyll content both under normal and salt stressed condition. The effect of exogenous T-Spm was more effective than Spm in plant growth and stress tolerance. The mutants varying in endogenous tetraamines content were also found to be different in response to stress (salt, osmotic and ionic) condition. Growth inhibition of spms mutant seedlings was minimum in compare to other mutants and wild type, probably due to higher amount of T-Spm content. Further to differentiate the tissue specific expression of tetraamines, histochemical GUS assay was performed using SPMS and ACL5 promoter:: GUS transgenic plants and the results indicate that the two tetraamines; spermine and thermospermine may play some different and specific role in respect to tissue specificity and stress responses.J. Bangladesh Agril. Univ. 16(2): 244-249, August 2018

Association of microinjected myosin and its subfragments with myofibrils in living muscle cells.

Purified skeletal muscle myosin was labeled with iodoacetamidofluorescein and microinjected into cultured chick myotubes. The fluorescent myosin analogue became incorporated within 10-15 min after injection, into either periodic (mean periodicity = 2.23 +/- 0.02 micron) bands or apparently continuous fibrillar structures. Comparison of rhodamine-labeled alpha-actinin with coinjected fluorescein-labeled myosin suggested that myosin fluorescence was localized at the A-bands of myofibrils. In addition, close examination of the fluorescent myosin bands indicated that they were composed of two fluorescent bars separated by a nonfluorescent line that corresponded to the H-zone. Once incorporated, the myosin underwent a relatively slow exchange along myofibrils as indicated by fluorescence recovery after photobleaching. Glycerinated myofibrils were able to bind fluorescent myosin in a similar pattern in the presence or absence of MgATP, indicating that actin-myosin interactions had little effect on this process. Fluorescent heavy meromyosin did not incorporate into myofibrillar structures after injection. Light meromyosin, however, associated with A-bands as did whole myosin. These results suggest that microinjected myosin, even with its relatively low solubility under the cytoplasmic ionic condition, is capable of association with physiological structures in living muscle cells. Additionally, the light meromyosin portion of the molecule appears to be mainly responsible for the incorporation.