Kappa caseína de la leche: aspectos bioquímicos, moleculares, productivos y nutricionales / Kappa casein of milk: productive, molecular, biochemical and nutritional aspects

La caseína hace parte de las proteínas secretadas en la leche de la mayoría de los mamíferos, es una fosfoproteína producida por cuatro genes que codifican para las caseínas a s1, a s2, β y κ, las cuales se organizan en forma de micelas o unidades solubles. Las caseínas tienen un alto contenido de aminoácidos esenciales que se separan de la parte acuosa por acción de enzimas como la quimosina, la cual precipita la proteína en la elaboración quesos. Dentro de la caseínas de la leche, la kappa-caseína tiene gran influencia en la composición de la leche en relación con su capacidad de coagulación, tiempo de formación del cuajo, tasa de formación de la cuajada, y vigor del coágulo en la producción de queso para consumo humano. El conocimiento de los factores que definen el nivel de kappa caseína en la leche es de relevancia para los productores y procesadores, puesto que la elevación de su contenido puede derivar en un mayor rendimiento del producto para la elaboración de derivados lácteos y, a su vez, en un mayor beneficio económico.

Casein is a phosphoprotein secreted in the milk of most mammal species. It belongs to a group of proteins coded by four genes, namely a s1, a s2, β and κ, which are organized in micelles or soluble units. Proteins from this group have a high content of essential amino acids. These molecules are separated by precipitation from the aqueous part by enzymes, such as chymosin, during the production of cheese. Moreover, the caseins, kappa-casein plays a major role on milk coagulation, thus, influencing the rennet formation time, the curd production rate and the consistency of cheese made for human consumption. Knowledge on the factors involved in regulating kappa-casein levels in milk, is of the most relevant aspects to milk producers and dairy product manufacturers given that an increase in its content, may improve milk yield and finally, economic profit.

Role of (pro)rennin receptor in cardiomyocytes of heart failure rat model / 华中科技大学学报（医学）（英德文版）

The role of (pro)rennin receptor (PRR) in cardiomyocytes of a heart failure (HF) rat model was studied. Spontaneously hypertensive rats (SHR) with HF (SHR-HF) or not were identified by two-dimensional (2-D) ultrasound. Age-matched Wistar Kyoto normotensive (WKY) rats were used as controls. PRR short hair RNA (sh-RNA) was injected into the heart of SHR-HF. Simultaneously SHR and controls received the same shRNA injection into the heart. Scramble shRNA was injected into the heart as controls. The expression of PRR mRNA and protein in cardiomyocytes was detected by using real-time PCR and Western blotting respectively. The heart function was evaluated by 2-D ultrasound, including eject fraction (EF%), fractional shortening (FS%), left ventricle thickness (LV), and inter-ventricular septal thickness (IVS). The number of apoptotic cardiomyocytes was counted by using flow cytometry. The results showed that the mRNA and protein expression levels of PRR were significantly higher in cardiomyocytes of SHR-HF group than in those of SHR group or control group. The apoptosis of myocytes in SHR-HF group was increased as compared with SHR group or control group. After knock-down of PRR with shRNA in SHR-HF group, the apoptosis of myocytes was reduced, resulting in the improved heart function. It was suggested that down-regulation of PRR might protect the heart from development of HF in SHR-HF by inhibiting the apoptosis of cardiomyocytes.

Influence of non-sodium restricted diet with diuretics on plasma rennin, renal blood flow and in patients with cirrhotic ascites / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To explore influence of sodium restricted diet and non-sodium restricted diet on plasma rennin (PRA), angiotensin II (All), ALD, renal blood flow (RBF) and subside of ascites in patients with cirrhotic ascites.</p><p><b>METHODS</b>Eighty cases of hepatitis B with cirrhotic ascites were randomly divided into sodium restricted diet group and non-sodium restricted diet group. 39 cases were in non-sodium restricted diet group, taking sodium chloride 6500-8000 mg daily; 41 cases were in sodium restricted diet group, taking sodium chloride 5000 mg daily. Both groups received diuretics furosemide and spironolactone. Blood sodium, urine sodium, PRA, AII, ALD, RBF ascites subsiding were compared after treatment.</p><p><b>RESULTS</b>In non-sodium restricted diet group, blood sodium and urine sodium increased 10 days after treatment compared with those before treatment, and compared with those of sodium restricted diet group 10 days after treatment, P <0. 01. RBF increased compared with that before treatment, and compared with that of sodium restricted diet group 10 days after treatment, P < 0. 01. Renal damage induced by low blood sodium after treatment was less in non-sodium restricted diet group than that in sodium restricted diet group, P <0. 05. Ascites disappearance upon discharge was more in sodium restricted diet group than that in non-sodium restricted diet group, P <0. 01. Time of ascites disappearance was shorter in non-sodium restricted diet group than that in sodium restricted diet group, P < 0. 01.</p><p><b>CONCLUSION</b>Compared with sodium restricted diet, while using diuretics of both groups, non-sodium restricted diet can increase level of blood sodium, thus increasing excretion of urine sodium and diuretic effect. It can also decrease levels of PRA, AII and ALD, increase renal blood flow and prevent renal damage induced by low blood sodium and facilitate subsiding of ascites.</p>

Two Case of Primary Aldosteronism Induced by Aldosterone Producing Adrenal Adenoma in a Family

Primary aldosteronism, is defined as a group of disorders characterized by the excess of aldosteron, with suppressed rennin activity, resulting in hypertension and hypokalemia. In most cases, primary aldosteronism is sporadic due to a unilateral adrenal adenoma or bilateral adrenal hyperplasia. Familial hyperaldosteronism is a rare cause of primary aldosteronism and its prevalence has not been established well. We describe two cases of primary aldosteronism in a family involving a sister and brother due to an aldosterone producing adenoma in the left adrenal gland. Their hypokalemia and hypertension were cured by complete resection of the adrenal adenoma. Genetic analyses could not be done because of patients' rejection.

Gene synthesis of the bovine prochymosin gene and high-level expression in Kluyvermyces lactis / 生物工程学报

Chymosin is an important industrial enzyme widely used in cheese manufacture. To improve expression efficiency of recombinant bovine chymosin in Kluyveromyces lactis strain GG799, we designed and synthesized a DNA sequence encoding bovine prochymosin gene (GenBank Accession No. AA30448) by using optimized codons. The synthesized prochymosin gene was amplified by two-step PCR method, and then cloned into the expression vector pKLAC1, resulting in pKLAC1-Prochy. pKLAC1-Prochy was linearized and transformed into K. lactis GG799 by electrotransformation. Positive clones were screened by YEPD plates containing 1% casein. A recombinant strain chyl with highest activities and multi-copy integration which was detected by using specifical integration primers was chosen and fermented in flask. Prochymosin was expressed in K. lactis successfully. SDS-PAGE analysis revealed that the purified recombinant bovine prochymosin had a molecular mass of 41 kDa. After acid treatment, molecular weight of chymosin is about 36 kDa, the same as native bovine chymosin. Activity tests showed that the chymosin activity of the culture supernatant was 99.67 SU/mL after 96 h cultivation. The activities of chymosin were not prominent increased when galactose was used as carbon source instead of glucose, which proved that the fermentation of recombinant strain does not need galactose inducing. The recombinant K. lactis strain obtained in this study could be further used to produce recombinant chymosin for cheese making.

Isolation of high quality DNA: a protocol combining “rennet” and glass milk

High quality DNA is essential for many molecular biology techniques. However, the reagents used for that purpose usually are expensive and/or cause a high environmental impact. Here, we describe two alternative protocols that use inexpensive reagents and are not hazardous to the environment. The first protocol utilizes the enzyme chymosin, normally used as “rennet” in cheese production and which is easily obtained on the commercial market. The second protocol uses “rennet DNA extraction protocol” combined with the DNA binding capacity of glass powder (glass milk), which can easily be “home made”. The first protocol is used when a high yield of DNA is needed, whereas the second protocol is used for production of a higher quality DNA, being able to work with sparse samples.

ANCA-related crescentic glomerulonephritis in a patient with systemic sclerosis / 대한내과학회지

The renal manifestations of systemic sclerosis include proteinuria, hypertension, azotemia, and renal crisis. Two types of scleroderma renal crisis (SRC) are recognized. Typical SRC is a syndrome consisting of acute-onset malignant hypertension accompanied by rapidly progressive renal failure, hypertensive retinopathy, and elevated plasma renin activity. The other type is normotensive renal failure, which is generally accompanied by antineutrophil cytoplasmic autoantibody (ANCA)-positive crescentic glomerulonephritis. A 51-year-old woman with scleroderma without marked dermatological change developed ANCA-related renal failure. She had neither malignant hypertension nor an elevated plasma rennin concentration. Renal biopsy showed crescentic glomerulonephritis (pauci-immune type), and the myeloperoxidase-specific ANCA (MPO-ANCA) titer was elevated at 1015 AAU. She was cured using steroid pulse therapy, combined with an angiotensin-converting-enzyme inhibitor and angiotensin-II receptor blocker

Recombinant expression of bovine chymosin in Pichia pastoris / 生物工程学报

To express bovine chymosin in yeast, we amplified the prochymosin gene from the plasmid pMD18T-Prochy by PCR, and then cloned the gene into the expression vector pPICZaA, resulting in pPICZaA-Prochy. Pichia pastoris GS115 was used as host cells. Integration of the prochymosin cDNA into the Pichia pastoris genome was confirmed by PCR and sequencing analysis. Chymosin was expressed in Pichia pastoris successfully, and a strong band at about 37 kD was shown by SDS-PAGE. Activity tests showed that the chymosin activity of the culture supernatant was 12.2 SU/mL. This is the first report of successful expression of chymosin in Pichia pastoris. The recombinant Pichia pastoris strain obtained in this study could be further used to produce recombinant chymosin for cheese making.

A Case of Male Pseudohermaphroditism due to 17alpha-Hydroxylase Deficiency / 대한불임학회지

Female phenotype of a 46,XY male may originates from male pseudohermaphroditism due to 17alpha-hydroxylase deficiency. Lack of cortisol increases adrenocorticotropic hormone (ACTH) and mineralocorticoid production, leading to low renin hypertention and hypokalemia. A 41-year-old phenotypic female presented primary amenorrhea and hypertension. In the hormonal profile, the levels of serum estradiol, testosterone, rennin, and cortisol were decreased and ACTH and deoxycorticosterone were increased. Laparoscopic bilateral gonadectomy was performed, and corticosteroid, antihypertensive drugs, and estrogen were administered. We report this case with a brief review of the literatures.

A Case of Licorice Induced Hypokalemic Paralysis with Rhabdomyolysis / 대한내분비학회지

Prolonged ingestion of licorice can cause hypermineralocorticoidism, with sodium retention, potassium loss and hypertension. Nevertheless, its initial presentation with a very severe degree of hypokalemic paralysis and rhabdomyolysis are exceedingly rare. We describe a patient who experienced hypokalemic paralysis and rhabdomyolysis after licorice ingestion. The patient's initial blood pressure was 160/80mmHg. The major biochemical abnormalities included; hypokalemia(K+ 1.3mEq/L), metabolic alkalosis, with a pH of 7.64, and urine myoglobin > 3000ng/mL. The plasma rennin activity and aldosterone level were suppressed. The 24 hour urine cortisol concentration was normal. The patients, over a 1 month period, had ingested 500g of licorice boiled in water. After quitting the licorice, the hypokalemia and muscle paralysis gradually improved and blood pressure returned to normal

Características de la producción de la renina microbiana de Mucor miehei en un proceso de alimentación por lote / Mucor miehei's microbial rennin production characteristics in a fed-batch proccess

El moho zigomiceto Mucor miehei produce una proteasa de tipo ácido (EC: 3.4.23.10) semejante a la renina o cuajo de ternero. Se ha encontrado que la síntesis de la enzima está parcialmente asociada al crecimiento, y que altas velocidades de consumo de glucosa dan como resultado una mayor producción de la renina microbiana (Escobar and Barnett, 1993, 1995). Durante el proceso de produc-ción de la proteasa se observó que cuando la velocidad de producción de la misma aún es alta, los niveles de glucosa alcanzan a ser mínimos, niveles que se consideraron como una de las posibles causas de la finalización de la produc-ción de la enzima (Escobar and Barnett, 1993,1995). Frente a esta limitación fisiológica, se planteó un proceso de dos etapas para mejorar la producción de la proteasa y superar el fenómeno mencionado.La primera consistió en estudiar la relación entre la pro-ducción de la renina y el consumo de azúcares (especial-mente la glucosa) en el transcurso de la fermentación, para determinar aquellos momentos en los que la rata de pro-ducción de enzima es alta y la concentración de glucosa se encuentra cercana a cero. En la segunda etapa se aplicó un proceso de alimentación por lote de glucosa durante esos momentos, para observar si la producción de la enzi-ma aumentaba.Se obtuvo un valor máximo de actividad enzimática (AE) de 165 unidades coagulantes (UC)/ml para el proceso en cochada y una velocidad de consumo de azúcares prome-dio de 0,1813 g de glucosa/1/h. Con base en los resultadosanteriores se determinaron condiciones para el proceso de alimentación por lote de glucosa, tales como veloci-dad, tiempo y concentración. Las condiciones para el pro-ceso de alimentación por lote fueron un flujo de 0,06 ml/ min y una concentración de glucosa de 50 g/1 sin obtener-se aumento considerable en el valor de la AE (95 UC/ml). Se obtuvo una concentración celular promedio de 11 g/1 y un rendimiento del nutriente en masa celular (YX/SA) pro-medio de 0,3 g de células/g...

Edam cheese manufacture with rennin-like enzyme from penicillium funiculosum

Fungal enzyme from Penicillium funiculosum E-NRC 629 a rennet substitute was used as milk clotting enzyme in the manufacture of Edam cheese from cow's milk. Resultant cheese was ripened for 90 days and analyzed when fresh and after 15, 30, 60 and 90 days of moisture content, acidity%, fat/DM, soluble nitrogen no-protein nitrogen, amino acid nitrogen, and total volatile fatty acid [TVFA]. Moreover, cheese was evaluated organoleptically. The obtained results showed that the breakdown of protein content, and TVFA was higher in Edam cheese made with fungal enzyme or its mixture rennet enzyme than in control cheese throughout the ripening period. Moreover, experimental cheese gained acceptable body with a good clean flavor during the ripening period. According to these studies it was concluded that using fungal enzyme of Penicillium funiculosum E-NRC 629 for Edam cheese manufacture is acceptable, it enhanced flavor development and improved cheese quality during ripening

Solubilización y renaturalización de la fusión superóxido dismutasa humana y proquimosina de ternero sintetizada en Saccharomyces cerevisiae / Solubilization and renaturation of human superoxide dismutase and call prochymosin gen fusion synthetized in saccharomyces cerevisiae

La proquimosina de ternero fusionada al gen de la superóxido dismutasa humana (SOD) fue sintetizada en forma insoluble en Saccharomyces cerevisiae. Las condiciones que permiten la solubilización de la proteína fueron investigada, siendo la desnaturalización el proceso esencial mediante el cual es solubilizado más del 90 % del producto recombinante. Se estudiaron diferentes parámetros que intervienen en el proceso de renaturalización de la SOD proquimosina, describiéndose un procesamiento mediante el cual es posible recuperar el 25 % de la proquimosina soluble en su forma nativa. Más del 98 % de la proteína fue activada, obteniéndose un preparado enzimático cuya función biológica fue determinada mediante el proceso de coagulaciónm de la leche

Producción de proquimisina bovina recombinante en Saccharomyces cerevisiae utilizando cultivo incrementado / Production of recombinant calf prochymosin in Sacharomyces cerevisiae using Fed-baytch culture

Se examinó el efecto de las condiciones de cultivo en la producción de la proteina fusionada SOD-proquimosina sintetizada en Sacharomyces cerevisiae bajo el control del fragmento corto del promotor que regula la síntesis de la enzima gliceraldehido-3-fosfato deshidrogenasa. El proceso fermentativo de 5 y 50 l de cultivo, obteniéndose resultados similares en ambas escalas. Cuando las células son cultivadas en medio selectivo suplementado con sacarosa al 5 % e hidrolizado de caseina al 2 % utilizando un sistema batch, la concentración relativa de SOD-proquimosina es incrementada 1,7 veces, mientras que la utilización del cultivo incrementado aumenta aproximadamente 4 veces la masa celular y eleva significativamente la producción de la proteina recombinante a un nivel del 2 % del total de la proteina celular

Expresión del gen de la quimosina en E. coli / Expression of the chymosin gene in E. coli

En este trabajo se describe la clonación y la expresión en E. coli del gen de la quimosina, enzima de importancia industrial para la producción de quesos. Los clones se identificaron analizando una genoteca de ADN complementario al ARN poli (A) proveniente del estómago de ternero, utilizando como sonda dos oligonucléotidos sintéticos. La región del gen, codificante a la proquimosina, fue expresada bajo el control del promotor triptófano. Se alcanzó una expresión equivalente al 10 % de la proteína total. La proteína fue detectada insoluble y formando cuerpos de inclusión. La enzima producida demostró tener propiedades semejantes a la natural.

1 Case of Primary Aldosteronism Caused by Adrenal Hyperplasia / 영남의대학술지

Primary aldosteronism is a disease that the stimulus for the excessive aldosterone production residues within the adrenal gland. It was first described by conn in 1955. And many cases were reported by physicians at present in the world. But it is relatively rare in Korea, probably due to lack of attention and medical facilities. Only about 13 cases have been reported at present. The clinical, biochemical feature in l case of primary aldosteronism caused by adrenal hyperplasia that was diagnosed at Yeungnam University Hospital was observed and the following result were obtained. 1. Clinical feature: The present case was 27-year-old woman who was admitted due to general weakness and easy fatigability. The above mentioned chief complaints occurred 8 months prior to admission when she delivered of second baby by cesarean section. Symptoms such as above chief complaints, intermittent muscle paralysis and cramping were noticed. Trousseau's sign was also present. The average blood pressure ranged from 170/90 to 200/120 2. Biochemical abnormalities: Severe hypokalemia lower than 2.5 mEq/L was presented and 24 hours urine potassium showed markedly increased urinary loss (228 mEq/day). Plasma rennin activity was decreased under normal range with furosemide administration. (Basal renin; 0.01 ng/ml/hr, stimulated rennin 0.12 ng/ml/hr). Saline suppression test revealed markedly elevated levels of aldosterone higher than normal range (Basal aldosterone; 320.68 pg/ml stimulated aldosterone; 451.86 pg/ml). And posture test showed decreased plasma rennin activity and increased plasma aldosterone level. 3. Adrenal CT scan revealed no abnormal findings. 4. Treatment and course: Spironolactione was given at OPD with regular follow-up. Her blood pressure ranged from 150/90 to 160/100 and symptoms were improved. The effect of treatment was satisfactory and further follow up would be performed.

Characterization of renninlike enzyme produced in submerged culture of aspergillus niger

Aspergillus migor produced powerful milk - clotting activity when it was grown aerobically in submerged cultures. The enzyme could be produced in sweet rennet buffalo whey and in salted whey media without extraneous- supplementation with other nutrients. Characterization studies on the activity produced in sweet whey media have revealed that the enzyme activity responded to dilution in a linear mainner, thus permitting the prio adjustment of the milkclotting time as desired. The addition of calcium chloride increased the milk-clotting activity many folds up to 0.08:1T a3 final concentration, whereas the incorporation of sodium chloride in the reaction mixture resulted in significant inhibition of the clotting reaction particularly at high concentrations. The enzyme was heat-tolerant up to 60. On the other hand, the milk-clotting reaction catalyzed by this enzyme had an optimum temperature range between 70§ to 80§, thus, suggesting, possible activity protection by the presence of the substrate. The results obtained are discussed in the light of the application feasibility of this eyzyme as a substitute for animal rennet