Digestion in the larger black flour beetle, Cynaeus angustus (LeConte), was studied to identify new control methods for this pest of stored grains and grain products. The physiological pH of the larval gut, as measured with extracts in water, was approximately 6.1, and the pH for optimal hydrolysis of casein by gut extracts was 6.2 when buffers were reducing. However, under non-reducing conditi...

The fluorescent proteinase transition-state analog inhibitor, dansyl-L-argininal (DnsArgH), may be a selective probe of cysteine and serine-type proteinases in a fibrosarcoma tumor cell line (HSDM1C1). DnsArgH binds with high affinity to proteinases because of its transition-state analog properties, and on association it gives a dramatically increased fluorescent yield. The DnsArgH binding is i...

Fertilization in sea urchins is followed by the replacement of sperm-specific histones by cleavage-stage histone variants recruited from maternal stores. Such remodelling of zygote chromatin involves a cysteine proteinase that degrades the sperm-specific histones in a selective manner, leaving the maternal cleavage-stage histone variants intact. The mechanism that determines the selectivity of ...

elsewhere. Amino acid analysis of avocado cystatin was first done. The amino acid composition derived from protein hydrolysatc was Asp7,s, Thr4.7, Ser6.3, Gluis.3, Pro2,D, Gly4.s, Alas.7, Valne, Meto.s, Ilei.p, Leub.6, Tyr2.7, Phe4,i, Lysg.s, His2.o, Arg3.6. The N-terminal amino acids of avocado cystatin up to position 50 was sequenced, as shown in Fig, 1, by a gas-phase sequencer (Applied Bios...

Several heterologous expression systems were tested for their ability to express a unique maize cysteine proteinase Mir1. A baculovirus-based expression system using Trichoplusia ni larvae as host resulted in the expression of Mir1 that was correctly processed and exhibited proteinase activity. Expression in Escherichia coli resulted in accumulation of Mir1, but it had limited solubility and en...