Primary antisera against selected steroids or proteins and secondary antisera against gamma-globulins--an available tool for studies of reproductive processes

This paper presents characteristics of different polyclonal antisera raised against several steroid and protein antigens: 1/ primary antisera against steroid hormones: estradiol-17beta (anti-E2), estrone (anti-E1), testosterone (anti-T), androstendione (anti-A4), cortisol (anti-F) and corticosterone (anti-B); 2/ primary antisera against porcine luteinizing hormone (anti-pLH) and against different forms of porcine pregnancy associated glycoproteins (anti-pPAG) - proteins produced by chorionic tissue; 3/ secondary monovalent antisera raised against rabbit gamma-globulins (Sm-r); 4/ secondary polyvalent antisera against rabbit, pig and quinea pig gamma-globulins mixed at a ratio 1:1:1 (Sp-rpq). All antisera described in the paper present sufficient quality to be routinely used in various RIA, ELISA or Western determinations in physiological and clinical studies of reproductive processes. The antisera against steroid hormones and pLH are available on request.     

Protein A of quinolinate synthetase is the site of oxygen poisoning of pyridine nucleotide coenzyme synthesis in Escherichia coli.

De novo biosynthesis of pyridine nucleotide coenzymes in Escherichia coli is initiated by an enzyme complex (quinolinate synthetase) containing protein B which converts -aspartate into iminoaspartate protein A, which then generates quinolinate on the pathway to the coenzymes. This complex has been shown to be poisoned by hyperbaric oxygen. ^7,8 We performed assays made dependent on both proteins B and A versus only protein A, using cell-free extracts of hyperbaric-oxygen poisoned and aerobically grown cells. The specific activities were produced by a similar amounts of 68% and 60%, respectively, when measured in assays made dependent on enzymes B and A versus only protein A that was derived from oxygen-poisoned extract. Thus, protein A is the oxygen-sensitive component.     

Structure and Function of the Escherichia coli Tol-Pal Stator Protein TolR

TolR is a 15-kDa inner membrane protein subunit of the Tol-Pal complex in Gram-negative bacteria, and its function is poorly understood. Tol-Pal is recruited to cell division sites where it is involved in maintaining the integrity of the outer membrane. TolR is related to MotB, the peptidoglycan (PG)-binding stator protein from the flagellum, suggesting it might serve a similar role in Tol-Pal. The only structure thus far reported for TolR is of the periplasmic domain from Haemophilus influenzae in which N- and C-terminal residues had been deleted (TolR(62–133), Escherichia coli numbering). H. influenzae TolR(62–133) is a symmetrical dimer with a large deep cleft at the dimer interface. Here, we present the 1.7-Å crystal structure of the intact periplasmic domain of E. coli TolR (TolR(36–142)). E. coli TolR(36–142) is also dimeric, but the architecture of the dimer is radically different from that of TolR(62–133) due to the intertwining of its N and C termini. TolR monomers are rotated ∼180° relative to each other as a result of this strand swapping, obliterating the putative PG-binding groove seen in TolR(62–133). We found that removal of the strand-swapped regions (TolR(60–133)) exposes cryptic PG binding activity that is absent in the full-length domain. We conclude that to function as a stator in the Tol-Pal complex dimeric TolR must undergo large scale structural remodeling reminiscent of that proposed for MotB, where the N- and C-terminal sequences unfold in order for the protein to both reach and bind the PG layer ∼90 Å away from the inner membrane.     

Peroxidase activity in non-embryogenic and embryogenic calli and in developing somatic embryos of white fir (Abies concolor Gord. et Glend)

ABSTRACT

Peroxidase activity was monitored during somatic embryogenesis of white fir (Abies concolor Gord. et Glend) starting from a non-embryogenic callus. Results revealed profound differences between non-embryogenic and embryogenic calli with an elevated level of enzyme activity in non-embryogenic ones. Precotyledonary, early cotyledonary and late cotyledonary stages of somatic embryogenesis were characterized by a substantially reduced peroxidase activity compared to callus tissues and regenerated plantlets. Changes in peroxidase activity are as a rule paralleled by variation in isoenzyme composition. The utility of the enzyme in the induction stage of somatic embryogenesis in white fir is proposed.     

Soluble tumour necrosis factor-α receptor type 1 as a biomarker of response to phototherapy in patients with psoriasis

Abstract

The purpose of the study was to analyze the relationship between the serum concentration of soluble tumour necrosis factor-α type 1 (sTNF-R1), the severity of plaque-type psoriasis and therapeutic response. We compared sTNF-R1 in 25 patients treated with narrowband ultraviolet B (NB-UVB) radiation and 25 patients treated with systemic photochemotherapy (psoralen plus UVA – PUVA). The pretreatment Psoriasis Area and Severity Index (PASI) score and sTNF-R1 concentration were 16.32±5.26 and 1.99±0.40 ng ml^?1, respectively, in the group treated with NB-UVB, and 17.22±3.48 and 2.07±0.31 ng ml^?1, respectively, in the group treated with PUVA. The concentration of sTNF-R1 in healthy controls was 1.49±0.34 ng ml^?1 (p<0.05 compared with patients with psoriasis). The pretreatment PASI score correlated with sTNF-R1 in both treatment groups (r=0.46 and r=0.44, p<0.05). NB-UVB and PUVA gave similar therapeutic effects (the PASI score after 20 treatments was 4.42±1.67 in the NB-UVB-treated group and 5.55±2.10 in PUVA-treated patients); however, the sTNF-R1 concentration at the same time differed significantly: 1.52±0.37 ng ml^?1 and 1.98±0.39 ng ml^?1 (p<0.001), respectively. Moreover, the decline in sTNF-R1 in both treatment groups was significant only in patients in whom the duration of skin lesions was less than 3 months. The results suggest that the value of serum sTNF-R1 concentration as a marker of response to phototherapy may depend on duration of skin lesions and the treatment method.     

Convergent Antibody Signatures in Human Dengue

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